Contribution of Cardiac MRI in the Diagnosis of Acute Myocarditis

Objective: To describe the MRI abnormalities observed in acute myocarditis. Materials and Methods: Retrospective cross-sectional study with a descriptive aim, carried out at the North Franche-Comte Hospital, over a period of 12 months, from January 2021 to December 2021. It covered all patients who received an MRI of heart disease and were diagnosed with myocarditis. The diagnosis of myocarditis was retained in all patients on the basis of two arguments: a T2 PSIR hyper signal and a late enhancement at 15 min in T1 PSIR with gadolinium. Results: Myocarditis was diagnosed in 20 patients out of a total of 214 who performed cardiac MRI, i.e. 10.30% of cases. The average age was 33.7 ± 14.3 with extremes of 17 and 69 years. We observed a male predominance with 11 men (55%) for 9 women (45%) or a sex ratio of 1.2. Clinical suspicion of myocarditis and acute coronary syndrome were the main indications for MRI. The lesion sites were subepicardial (95%) and/or intramural (30%), respecting the subendocardium, interesting for the majority, segments 12 (anterolateral) in 50% and/or 11 (inferolateral) in 43% of cases. Global hypokinesia was observed in 30% of patients associated with a decrease in LVEF. There was no cardiac volume abnormality or valvular abnormality. Conclusion: Cardiac MRI is nowadays the most efficient non-invasive imaging in the diagnosis of acute myocarditis. The diagnosis of myocarditis was made on 2 pathognomonic signs, namely a T2 STIR hyper signal and late enhancement at 15 min in T1 PSIR after injection of gadolinium. The morphology and lesion locations were in agreement with those described in previous studies. Global hypokinesia and pericardial effusion were observed in some patients. On the other hand, there was neither valvular anomaly, nor cardiac volume anomaly.

Is cardiac MRI an effective test for arrhythmogenic right ventricular cardiomyopathy diagnosis?

AIM:To evaluate the referrals with suspected arrhythmogenic right ventricular cardiomyopathy(ARVC)and compare cardiac MR(cMR)findings against clinical diagnosis.METHODS:A retrospective analysis of 114(age range16 to 83,males 55%and females 45%)patients referred for cMR with a suspected diagnosis of ARVC between May 2006 and February 2010 was performed after obtaining institutional approval for service evaluation.Reasons for referral including clinical symptoms and family history of sudden death,electrocardiogram and echo abnormalities,cMR findings,final clinical diagnosis and information about clinical management were obtained.The results of cMR were classified as major,minor,non-specific or negative depending on both functional and tissue characterisation and the cMR results were compared against the final clinical diagnosis.RESULTS:The most common reasons for referral included arrhythmias(30%)and a family history of sudden death(20%).Of the total cohort of 114 patients:4 patients(4%)had major cMR findings for ARVC,13patients(11%)had minor cMR findings,2 patients had non-specific cMR findings relating to the right ventricle and 95 patients had a negative cMR.Of the 4 patients who had major cMR findings,3(75%)had a positive clinical diagnosis.In contrast,of the 13 patients who had minor cMR findings,only 2(15%)had a positive clinical diagnosis.Out of the 95 negative patients,clinical details were available for 81 patients and none of them had ARVC.Excluding the 14 patients with no clinical data and final diagnosis,the sensitivity of the test was 100%,specificity 87%,positive predictive value29%and the negative predictive value 100%.CONCLUSION:CMR is a useful tool for ARVC evaluation because of the high negative predictive value as the outcome has a significant impact on the clinical decision-making.

Detection of Left Ventricular Cavity from Cardiac MRI Images Using Faster R-CNN

The automatic localization of the left ventricle(LV)in short-axis magnetic resonance(MR)images is a required step to process cardiac images using convolutional neural networks for the extraction of a region of interest(ROI).The precise extraction of the LV’s ROI from cardiac MRI images is crucial for detecting heart disorders via cardiac segmentation or registration.Nevertheless,this task appears to be intricate due to the diversities in the size and shape of the LV and the scattering of surrounding tissues across different slices.Thus,this study proposed a region-based convolutional network(Faster R-CNN)for the LV localization from short-axis cardiac MRI images using a region proposal network(RPN)integrated with deep feature classification and regression.Themodel was trained using images with corresponding bounding boxes(labels)around the LV,and various experiments were applied to select the appropriate layers and set the suitable hyper-parameters.The experimental findings showthat the proposed modelwas adequate,with accuracy,precision,recall,and F1 score values of 0.91,0.94,0.95,and 0.95,respectively.This model also allows the cropping of the detected area of LV,which is vital in reducing the computational cost and time during segmentation and classification procedures.Therefore,itwould be an ideal model and clinically applicable for diagnosing cardiac diseases.

Primary Cardiac Involvement in Scleroderma and Role of Cardiac MRI

Systemic sclerosis (scleroderma) is a connective tissue disease characterized by vascular dysfunction and fibrosis that can affect multiple organ systems. We present case of primary cardiac involvement and the diagnostic role of cardiac MRI. Cardiovascular magnetic resonance imaging (MRI) is an accurate, quantitative method for the non-invasive assessment of myocardial perfusion. The presence of clinically apparent myocardial involvement in scleroderma portends a very poor prognosis. One study of US veterans found that clinical cardiac disease in scleroderma was associated with a 70% mortality rate at five years. Management of heart failure and conduction system abnormalities in scleroderma is similar to other cardiac disease. It includes afterload reduction, beta-blockade, defibrillator placement, etc. Patients with reduced cardiac function and normal coronary arteries may benefit from increased immune suppresion.

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

Thrombolysis and extracorporeal cardiopulmonary resuscitation for cardiac arrest due to pulmonary embolism:A case report

BACKGROUND Cardiac arrest caused by acute pulmonary embolism(PE)is the most serious clinical circumstance,necessitating rapid identification,immediate cardiopulmonary resuscitation(CPR),and systemic thrombolytic therapy.Extracorporeal CPR(ECPR)is typically employed as a rescue therapy for selected patients when conventional CPR is failing in settings where it can be implemented.CASE SUMMARY We present a case of a 69-year-old male who experienced a prolonged cardiac arrest in an ambulance with pulseless electrical activity.Upon arrival at the emergency department with ongoing manual chest compressions,bedside pointof-care ultrasound revealed an enlarged right ventricle without contractility.Acute PE was suspected as the cause of cardiac arrest,and intravenous thrombolytic therapy with 50 mg tissue plasminogen activator was administered during mechanical chest compressions.Despite 31 minutes of CPR,return of spontaneous circulation was not achieved until 8 minutes after initiation of Veno-arterial extracorporeal membrane oxygenation(ECMO)support.Under ECMO support,the hemodynamic status and myocardial contractility significantly improved.However,the patient ultimately did not survive due to intracerebral hemorrhagic complications,leading to death a few days later in the hospital.CONCLUSION This case illustrates the potential of combining systemic thrombolysis with ECPR for refractory cardiac arrest caused by acute PE,but it also highlights the increased risk of significant bleeding complications,including fatal intracranial hemorrhage.

Differentiating between immune checkpoint inhibitor-induced myocarditis and cardiac metastasis in a cardio-oncology patient presenting with myocardial infarction: A case report

BACKGROUND Cardiovascular diseases and cancer are leading causes of morbidity and mortality.Patients with malignancies are at increased risk for cardiovascular complications including acute coronary syndromes,chemotherapy or radiation therapy related complications and cardiac metastasis.CASE SUMMARY We present a case of a 47-year-old female with metastatic cancer on immuno-therapy presented with anterior ST elevation myocardial infarction followed by emergent percutaneous coronary intervention in the left anterior descending artery.Echocardiography after 72 hours showed thickening of inferior wall and cardiac magnetic resonance depicted inflammation and necrosis attributable to either cardiac metastasis or immunotherapy induced myocarditis.Biopsy was not performed because of treatment with antiplatelet drugs and a definite diagnosis was achieved after probationary administration of high-dose intravenous methyl-prednisolone that led to recovery.CONCLUSION In patients with malignancy,chemotherapy-induced cardiovascular complications and cardiac metastasis are common concerns and may coexist with common acute cardiovascular diseases including acute coronary syndromes.In such cases clinical suspicion aided by multimodality imaging is crucial for the diagnosis.A multidisciplinary team approach is required for prompt initiation of the appro-priate treatment.

Chinese clinical practice consensus for device-supported treatment in adults with post-cardiac arrest syndrome(2024 Edition)

During cardiac arrest (CA),severe ischemia and hypoxia occur in tissues and organs of the entire body,inflammatory cytokines are released,and ischemiareperfusion injury occurs after the return of spontaneous circulation (ROSC),leading to multiple organ dysfunction in the body;this condition is called post-CA syndrome(PCAS).^([1])According to the BASeline Investigation of Out-of-Hospital Cardiac Arrest (BASIC-OHCA) study,the crude incidence of emergency medical service (EMS)-assessed OHCA was 95.7 per 100,000 individuals,and only1.2%of those individuals survived to hospital discharge or30 d after being resuscitated by the EMS in China.

Association between echocardiography utilization and prognosis in patients with cardiac arrest

Despite efforts to develop treatment technology for cardiac arrest (CA),CA incidence and mortality rates are still high.^([1,2])A recent study of CA patients in emergency departments revealed that the incidence of CA is increasing annually,and the in-hospital survival rate of CA patients is only approximately 28.7%.^([3])Echocardiography has been widely used as an important monitoring tool in critical care and helps to identify the cause of shock,monitor hemodynamics,and guide fluid therapy utilization.^([4])One study reported that approximately one-third of patients underwent formal echocardiography during hospitalization in the intensive care unit (ICU).

Real-world cost-effectiveness of targeted temperature management in out-of-hospital cardiac arrest survivors: results from an academic medical center

BACKGROUND: Targeted temperature management(TTM) is a common therapeutic intervention, yet its cost-effectiveness remains uncertain. This study aimed to evaluate the real-world cost-effectiveness of TTM compared with that of conventional care in adult out-of-hospital cardiac arrest(OHCA) survivors using clinical patient-level data.METHODS: We conducted a retrospective cohort study at an academic medical center in the USA to assess the cost-effectiveness of TTM in adult non-traumatic OHCA survivors between 1 January, 2019 and 30 June, 2023. The primary outcome was survival to hospital discharge. Incremental cost-effectiveness ratios(ICERs) were calculated and compared with various decision makers' willingness to pay. Cost-effectiveness acceptability curves were utilized to evaluate the economic attractiveness of TTM. Uncertainty about the incremental cost and effect was explored with a 95% confidence ellipse.RESULTS: Among 925 non-traumatic OHCA survivors, only 30(3%) received TTM. After adjusting for potential confounders, the TTM group did not demonstrate a significantly lower cost(delta cost-$5,141, 95% confidence interval [95% CI]: $-35,347 to $25,065, P=0.79) and higher survival to hospital discharge(delta effect 6%, 95% CI:-11% to 23%, P=0.41). Additionally, a 95% confidence ellipse indicated uncertainty reflected by evidence that the true value of the ICER could be in any of the quadrants of the cost-effectiveness plane.CONCLUSION: Although TTM did not demonstrate a clear survival benefit in this study, its potential cost-effectiveness warrants further investigation with larger sample sizes. These findings highlight the need for additional research to optimize TTM use in OHCA care and inform resource allocation decisions.

Macrophage polarization in cardiac transplantation:Insights into immune modulation and therapeutic approaches

The role and regulatory mechanisms of macrophage polarization in cardiac transplantation have gained significant attention.Macrophages can polarize into either the M1(pro-inflammatory)or M2(anti-inflammatory)phenotype in response to environmental cues.M1 macrophages facilitate transplant rejection by releasing inflammatory mediators and activating T cells,whereas M2 macrophages support graft survival by secreting antiinflammatory factors and promoting tissue repair.Mitochondrial quality control regulation plays a crucial role in macrophage polarization,which may influence graft survival and immune responses.This review provides an overview of the current understanding of mitochondrial quality control-regulated macrophage polarization in cardiac transplantation,its effects on graft outcomes,and potential therapeutic strategies to modulate this process to enhance transplant success rates.The review was conducted by systematically analyzing recent studies and integrating findings from key research articles to synthesize a comprehensive understanding of this emerging field.

Noninvasive Diagnosis of Cardiac Amyloidosis by MRI and Echochardiography

This study described the radiological features on echocardiography and MRI specific to cardiac amyloidosis confirmed on biopsy. Eleven cases of biopsy-proven cardiac amyloidosis were retrospectively reviewed in this study. All patients underwent biopsy, cardiac MRI and echocardiography. The main echocardiography and MRI findings were as follows: diffuse ventricular and septum wall thickening, atrial enlargement, pericardial effusion, restricted left ventricular (LV) systolic and diastolic function, characteristic granular sparkling of myocardium. MRI revealed a characteristic pattern of global subendocardial late enhancement, extending in varying degrees into the neighboring myocardium. The findings agreed with the infiltration distribution of amyloid protein. Typical abnormalities seen on echocardiography and MRI should have important diagnostic and prognostic value of cardiac amyloidosis. MRI should be considered in the diagnosis of cardiac amyloidosis if echocardiographic features are suspicious.

Effects of Amrinone on Cardiac Contraction and Relaxation in Isolated，Perfused Rat Heart

The effects of amrinone on cardiac contraction and relaxation were assessed in isolated, perfused rat hearts. It was found that the left ventricular developed pressure (LVDP), dp/dtmax and -da/dtmax did not significantly increase . and the time constant (τ) did not markedly shorten with perfusion of low concentration ( 1 nmol/L , 100 nmol/L) of amrinone. The perfusion with higher concentration (1000 nmol/L) of amrinone reduced LVDP (P<0. 01 ) ,dp/dtmax (P<0.01) , -dp/dtmax (P<0. 01). and prolonged τ(P< 0. 05) significaiatly. It was assumed that amrinone has no direct positive inotropic effect. and can not improve cardiac relaxation. On the contrary, the cardiac contraction and relax ation will be inhibited at higher concentration of amrinone.

The association between C-reactive protein to albumin ratio and 6-month neurological outcome in patients with in-hospital cardiac arrest

The global incidence rates of in-hospital cardiac arrest(IHCA)range from1.2 to 9.0 per1,000 hospitalized patients,as per the National Cardiac Arrest Database.[1] While IHCAs tend to exhibit superior 30-day survival rates relative to out-of-hospital cardiac arrests (OHCA) due to situational advantages,such as immediate access to medical personnel and treatments.

Cardiac arrest, stony heart, and cardiopulmonary resuscitation: An updated revisit

The post-resuscitation period is recognized as the main predictor of cardiopul-monary resuscitation(CPR)outcomes.The first description of post-resuscitation syndrome and stony heart was published over 50 years ago.Major manifestations may include but are not limited to,persistent precipitating pathology,systemic ischemia/reperfusion response,post-cardiac arrest brain injury,and finally,post-cardiac arrest myocardial dysfunction(PAMD)after successful resuscitation.Why do some patients initially survive successful resuscitation,and others do not?Also,why does the myocardium response vary after resuscitation?These ques-tions have kept scientists busy for several decades since the first successful resuscitation was described.By modifying the conventional modalities of resu-scitation together with new promising agents,rescuers will be able to salvage the jeopardized post-resuscitation myocardium and prevent its progression to a dismal,stony heart.Community awareness and staff education are crucial for shortening the resuscitation time and improving short-and long-term outcomes.Awareness of these components before and early after the restoration of circulation will enhance the resuscitation outcomes.This review extensively addresses the underlying pathophysiology,management,and outcomes of post-resuscitation syndrome.The pattern,management,and outcome of PAMD and post-cardiac arrest shock are different based on many factors,including in-hospital cardiac arrest vs out-of-hospital cardiac arrest(OHCA),witnessed vs unwitnessed cardiac arrest,the underlying cause of arrest,the duration,and protocol used for CPR.Although restoring spontaneous circulation is a vital sign,it should not be the end of the game or lone primary outcome;it calls for better understanding and aggressive multi-disciplinary interventions and care.The development of stony heart post-CPR and OHCA remain the main challenges in emergency and critical care medicine.

Safety and effectiveness of neuromuscular electrical stimulation in cardiac surgery:A systematic review

BACKGROUND Lack of mobilization and prolonged stay in the intensive care unit(ICU)are major factors resulting in the development of ICU-acquired muscle weakness(ICUAW).ICUAW is a type of skeletal muscle dysfunction and a common complication of patients after cardiac surgery,and may be a risk factor for prolonged duration of mechanical ventilation,associated with a higher risk of readmission and higher mortality.Early mobilization in the ICU after cardiac surgery has been found to be low with a significant trend to increase over ICU stay and is also associated with a reduced duration of mechanical ventilation and ICU length of stay.Neuromuscular electrical stimulation(NMES)is an alternative modality of exercise in patients with muscle weakness.A major advantage of NMES is that it can be applied even in sedated patients in the ICU,a fact that might enhance early mobilization in these patients.AIM To evaluate safety,feasibility and effectiveness of NMES on functional capacity and muscle strength in patients before and after cardiac surgery.METHODS We performed a search on Pubmed,Physiotherapy Evidence Database(PEDro),Embase and CINAHL databases,selecting papers published between December 2012 and April 2023 and identified published randomized controlled trials(RCTs)that included implementation of NMES in patients before after cardiac surgery.RCTs were assessed for methodological rigor and risk of bias via the PEDro.The primary outcomes were safety and functional capacity and the secondary outcomes were muscle strength and function.RESULTS Ten studies were included in our systematic review,resulting in 703 participants.Almost half of them performed NMES and the other half were included in the control group,treated with usual care.Nine studies investigated patients after cardiac surgery and 1 study before cardiac surgery.Functional capacity was assessed in 8 studies via 6MWT or other indices,and improved only in 1 study before and in 1 after cardiac surgery.Nine studies explored the effects of NMES on muscle strength and function and,most of them,found increase of muscle strength and improvement in muscle function after NMES.NMES was safe in all studies without any significant complication.CONCLUSION NMES is safe,feasible and has beneficial effects on muscle strength and function in patients after cardiac surgery,but has no significant effect on functional capacity.

Left bundle branch pacing set to outshine biventricular pacing for cardiac resynchronization therapy?

The deleterious effects of long-term right ventricular pacing necessitated the search for alternative pacing sites which could prevent or alleviate pacinginduced cardiomyopathy.Until recently,biventricular pacing(BiVP)was the only modality which could mitigate or prevent pacing induced dysfunction.Further,BiVP could resynchronize the baseline electromechanical dssynchrony in heart failure and improve outcomes.However,the high non-response rate of around 20%-30%remains a major limitation.This non-response has been largely attributable to the direct non-physiological stimulation of the left ventricular myocardium bypassing the conduction system.To overcome this limitation,the concept of conduction system pacing(CSP)came up.Despite initial success of the first CSP via His bundle pacing(HBP),certain drawbacks including lead instability and dislodgements,steep learning curve and rapid battery depletion on many occasions prevented its widespread use for cardiac resynchronization therapy(CRT).Subsequently,CSP via left bundle branch-area pacing(LBBP)was developed in 2018,which over the last few years has shown efficacy comparable to BiVP-CRT in small observational studies.Further,its safety has also been well established and is largely free of the pitfalls of the HBP-CRT.In the recent metanalysis by Yasmin et al,comprising of 6 studies with 389 participants,LBBPCRT was superior to BiVP-CRT in terms of QRS duration,left ventricular ejection fraction,cardiac chamber dimensions,lead thresholds,and functional status amongst heart failure patients with left bundle branch block.However,there are important limitations of the study including the small overall numbers,inclusion of only a single small randomized controlled trial(RCT)and a small follow-up duration.Further,the entire study population analyzed was from China which makes generalizability a concern.Despite the concerns,the meta-analysis adds to the growing body of evidence demonstrating the efficacy of LBBP-CRT.At this stage,one must acknowledge that the fact that still our opinions on this technique are largely based on observational data and there is a dire need for larger RCTs to ascertain the position of LBBPCRT in management of heart failure patients with left bundle branch block.

Cardiac rehabilitation after cardiac surgery:An important underutilized treatment strategy

Physical inactivity remains in high levels after cardiac surgery,reaching up to 50%.Patients present a significant loss of functional capacity,with prominent muscle weakness after cardiac surgery due to anesthesia,surgical incision,duration of cardiopulmonary bypass,and mechanical ventilation that affects their quality of life.These complications,along with pulmonary complications after surgery,lead to extended intensive care unit(ICU)and hospital length of stay and significant mortality rates.Despite the well-known beneficial effects of cardiac rehabilitation,this treatment strategy still remains broadly underutilized in patients after cardiac surgery.Prehabilitation and ICU early mobilization have been both showed to be valid methods to improve exercise tolerance and muscle strength.Early mobilization should be adjusted to each patient’s functional capacity with progressive exercise training,from passive mobilization to more active range of motion and resistance exercises.Cardiopulmonary exercise testing remains the gold standard for exercise capacity assessment and optimal prescription of aerobic exercise intensity.During the last decade,recent advances in healthcare technology have changed cardiac rehabilitation perspectives,leading to the future of cardiac rehabilitation.By incorporating artificial intelligence,simulation,telemedicine and virtual cardiac rehabilitation,cardiac surgery patients may improve adherence and compliance,targeting to reduced hospital readmissions and decreased healthcare costs.

Nonlinear profile order for three-dimensional hybrid radial acquisition applied to self-gated free-breathing cardiac cine MRI

This paper presents a nonlinear profile order scheme for three-dimensional（3D） hybrid radial acquisition applied to self-gated, free-breathing cardiac cine magnetic resonance imaging（MRI）. In self-gated, free-breathing cardiac cine MRI,respiratory and cardiac motions are unpredictable during acquisition, especially for retrospective reconstruction. Therefore,the non-uniformity of the k-space distribution is an issue of great concern during retrospective self-gated reconstruction. A nonlinear profile order with varying azimuthal increments was provided and compared with the existing golden ratio-based profile order. Optimal parameter values for the nonlinear formula were chosen based on simulations. The two profile orders were compared in terms of the k-space distribution and phantom and human image results. An approximately uniform distribution was obtained based on the nonlinear profile order for persons with various heart rates and breathing patterns.The nonlinear profile order provides more stable profile distributions and fewer streaking artifacts in phantom images. In a comparison of human cardiac cine images, the nonlinear profile order provided results comparable to those provided by the golden ratio-based profile order, and the images were suitable for diagnosis. In conclusion, the nonlinear profile order scheme was demonstrated to be insensitive to various motion patterns and more useful for retrospective reconstruction.

Integrated Assessment of Cardiac PET/MRI: Co-Registered PET and MRI Polar Plots by Mutual MR-Based Segmentation of the Left Ventricular Myocardium

Background: In the present study, we sought to describe a procedure for the creation of co-registered positron emission tomography (PET) and magnetic resonance imaging (MRI) polar plots of cardiac PET/MRI examinations, validate the resulting plots against available standard methods in patients with myocardial infarction and provide examples that demonstrate the advantage of the novel approach over existing standards. Methods: Co-registered LGE and PET short-axis images were transformed into polar maps based on a radial sampling pattern. LGE was automatically detected using an automated thresholding algorithm (ATA). In 20 PET/MRI examinations in patients with acute myocardial infarction, agreement between manual LGE assessment and the ATA classification was calculated. Also agreement between MRI-segmentation based PET polar plots and standard PET polar plots (created with the Corridor4DM software package) was assessed. Results: No statistically significant difference in infarct sizes between manual and ATA segmentation was found (p = 0.12). Both methods were highly correlated (Pearson’s r = 0.96, p Conclusion: A straightforward software approach for the creation of co-registered PET and MRI polar plots was described and successfully demonstrated in PET/MRI studies of myocardial infarction and inflammation.