Incidence and peri-operative risk factors for development of acute kidney injury in patients after cardiac surgery:A prospective observational study

BACKGROUND Patients admitted to intensive care unit(ICU) after cardiac surgery develop acute kidney injury(AKI) immediately post-operation. We hypothesized that AKI occurs mainly due to perioperative risk factors and may affect outcome.AIM To assess peri-operative risk factors for AKI post cardiac surgery and its relationship with clinical outcome.METHODS This was an observational single center, tertiary care setting study, which enrolled 206 consecutive patients, admitted to ICU after cardiac surgery. Patients were followed-up until ICU discharge or death, in order to determine the incidence of AKI, perioperative risk factors for AKI and its association with outcome.Univariate and multivariate logistic regression analysis was performed to assess predictor variables for AKI development.RESULTS After ICU admission, 55 patients(26.7%) developed AKI within 48 h. From the logistic regression analysis performed, high EuroScore Ⅱ(OR: 1.18;95%CI: 1.06-1.31, P = 0.003), white blood cells(WBC) pre-operatively(OR: 1.0;95%CI: 1.0-1.0, P = 0.002) and history of chronic kidney disease(OR: 2.82;95%CI: 1.195-6.65, P = 0.018) emerged as independent predictors of AKI among univariate predictors. AKI that developed AKI had longer duration of mechanical ventilation [1113(777–2195) vs 714(511–1020) min, P = 0.0001] and ICU length of stay [70(28–129) vs 26(21–51) h, P = 0.0001], higher rate of ICU-acquired weakness(16.4% vs 5.3%, P =0.015), reintubation(10.9% vs 1.3%, P = 0.005), dialysis(7% vs 0%, P = 0.005), delirium(36.4% vs 23.8%, P = 0.001) and mortality(3.6% vs 0.7%, P = 0.046).CONCLUSION Patients present frequently with AKI after cardiac surgery. EuroScore Ⅱ, WBC count and chronic kidney disease are independent predictors of AKI development. The occurrence of AKI is associated with poor outcome.

Application progress of nursing intervention in cardiac surgery

As a stressor,cardiac surgery affects the physiology and psychology of patients,as well as their postoperative recovery.Patients tend to worry about cognitive deficiency,pain,discomfort,the risk of death,sleep,complications,and other factors,resulting in stress and anxiety.Moreover,serious adverse events,such as circulatory and respiratory dysfunction and infection,tend to occur after cardiac surgery and increase the economic burden on patients.Therefore,appropriate nursing interventions should be selected to strengthen patients’cognitive levels,compliance,and postoperative practices to accelerate their recovery,reduce complications,and shorten hospital stays so as to contribute to patients’lives and health.

Short- and Long-Term Outcomes of Cardiac Surgery in Kidney Transplant Recipients: A Review—Kidney Transplant and Cardiac Surgery

Background: Cardiovascular diseases remain the leading cause of death in kidney transplant patients and increasing proportion of these patients are referred to cardiac surgery. Data on short- and long-term outcomes of these patients are limited to single center reports with no randomized trials and no prospective studies published previously. The aim of this review was to report both short- and long-term outcomes of these patients. Methods: Literature review was conducted using three databases from inception to June 2022. Multiple search terms were used and limited to English language. Thirty-one relevant articles were included. Outcomes of interest were short-term mortality, long-term survival, renal allograft failure and infection in kidney transplant patients undergoing cardiac surgery. Results: Cardiac risk factors (diabetes mellitus, hypertension, hyperlipidemia) were prevalent in kidney transplant patients. 30-days mortality ranged across the studies from zero to 18.8%. The 1-year survival ranged from 71% - 97% and 5-years survival ranged from 31% - 95.7%. Commonest causes of death were cardiac and sepsis. Multiple predictors of mortality were reported. Postoperative acute kidney injury ranged from 0 - 74% with most of them being transient. Kidney graft failure ranged from 0 - 45% with 5-year kidney graft survival rates ranged between 37% - 80%. Post-operative infection rates ranged from 1% - 25% and the most common sites were pneumonia followed by septicemia and surgical site infections. Conclusion: Cardiac surgery can be performed in kidney transplant patients with good short- and long-term results.

The effect of head and facial massage on sleep condition after coronary artery bypass graft surgery

Background:Sleep disorders after heart surgery lead to increased heart rate,myocardial oxygen demand,and cause dysrhythmia that worsens heart ischemia.The purpose of this study was to determine the effect of head and facial massage on sleep conditions following coronary artery bypass graft surgery.Materials and methods:A randomized controlled trial was performed on 72 patients.They were randomly divided into interventional(n=36)and control groups(n=36).On the third to fifth day after the operation,head and the facial massage were done for 15 min in the intervention group.The patients in the control group received only routine care.Richard Campbell’s Sleep Questionnaire was completed for four consecutive days for each group.Data were analyzed in SPSS V26.Results:Mean scores for sleep conditions before the intervention no statistically significant difference seen between the two groups(P>0.05).After the intervention,there was a statistically significant difference between mean scores for sleep conditions of the interventional and control groups(P<0.001).Also with general estimated equation test compared mean scores for sleep conditions between two groups.That revealed sleep condition total score in the intervention group was more than the control group and the trend of changes over time was statistically significant(P<0.001).Conclusion:Head and facial massage is an effective nursing intervention in improving the sleep condition of patients after coronary artery bypass graft.Due to the fact that head and face massage is an easy method and brings patient satisfaction,it is recommended to use this method as a suitable supplement for drug therapy and postoperative interventions in these patients.

Randomized controlled trial of remote ischemic preconditioning and atrial fibrillation in patients undergoing cardiac surgery

AIM To study whether remote ischemic preconditioning(RIPC) has an impact on clinical outcomes, such as post-operative atrial fibrillation(POAF).METHODS This was a prospective, single-center, single-blinded,randomized controlled study. One hundred and two patients were randomized to receive RIPC(3 cycles of 5 min ischemia and 5 min reperfusion in the upper arm after induction of anesthesia) or no RIPC(control). Primary outcome was POAF lasting for five minutes or longer during the first seven days after surgery. Secondary outcomes included length of hospital stay, incidence of inpatient mortality, myocardial infarction, and stroke. RESULTS POAF occurred at a rate of 54% in the RIPC group and 41.2% in the control group(P = 0.23). No statistically significant differences were noted in secondary outcomes between the two groups. CONCLUSION This is the first study in the United States to suggest that RIPC does not reduce POAF in patients with elective or urgent cardiac surgery. There were no differences in adverse effects in either group. Further studies are required to assess the relationship between RIPC and POAF.

Hypoxic hepatitis in children after cardiac surgery

To the Editor: Hypoxic hepatitis(HH), also known as ischemic hepatitis or shock liver, is a liver injury characterized by necrosis of centrilobular hepatocytes with a rapid increase in serum aminotransferase levels. The incidence rate of HH among patients in the intensive care unit(ICU) was found to be 0.9%-11.9% [1]. Occurrence of HH appears to have a significant impact on the clinical outcome.

Isogeometric Analysis of Hyperelastic Material Characteristics for Calcified Aortic Valve

This study explores the implementation of computed tomography(CT)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcatheter heart valve replacement(TAVR)procedures.In order to facilitate this exploration,it derives pertinent formulas for 3D multi-material isogeometric hyperelastic analysis based on Hounsfield unit(HU)values,thereby unlocking foundational capabilities for isogeometric analysis in calcified aortic valves.A series of uniaxial and biaxial tensile tests is executed to obtain an accurate constitutive model for calcified active valves.To mitigate discretization errors,methodologies for reconstructing volumetric parametric models,integrating both geometric and material attributes,are introduced.Applying these analytical formulas,constitutive models,and precise analytical models to isogeometric analyses of calcified valves,the research ascertains their close alignment with experimental results through the close fit in displacement-stress curves,compellingly validating the accuracy and reliability of the method.This study presents a step-by-step approach to analyzing themechanical characteristics of patient-specific valves obtained fromCT images,holding significant clinical implications and assisting in the selection of treatment strategies and surgical intervention approaches in TAVR procedures.

Thoracoscopic resection of giant left atrial appendage aneurysm: A case report

Left atrial appendage aneurysm(LAAA)was first reported in the 1960s.1 LAAA is a rare condition,with just over 100 congenital or acquired cases reported to date.2 LAAA is frequently diagnosed incidentally during echocardiography or computed tomography(CT)scans.Most patients with LAAA are asymptomatic,while a few exhibit nonspecific symptoms,such as dyspnea,palpitation,and chest tightness.Patients with LAAA frequently present with atrial arrhythmias and systemic thromboembolism,such as stroke or multiorgan infarctions,due to the formation of a left atrial appendage thrombus.3 The lesion may be cured using aneurysm resection.Considering it as the potential cause of atrial arrhythmias and thromboembolism,the lesion must be identified on time and cured using a suitable treatment approach.

Acute Coronary Syndrome of Young Subjects at the Luxembourg Mother-Child University Hospital in Bamako

Introduction: Acute coronary syndrome is often the first event of coronary disease of young subjects. Objective: To study sociodemographic, clinical, paraclinical, therapeutic and evolutionary aspects of acute coronary syndrome of young subjects. Patients and Methods: Descriptive cross-sectional study with prospective recruitment from October 01, 2020 to March 31, 2022. Were included all patients admitted for acute coronary syndrome whose age was less or equal to 45 years and who had undergone coronary angiography at the Mother-Child University Hospital on Luxembourg from Bamako. Results: During the study period, we collected 60 patient files out of 198. These 60 patient files met our inclusion criteria. Hospital frequency was 30.30%. Average age of patients was 40.43 ± 3.9 years. Sex ratio M/F was 5.3. Main cardiovascular risk factor was smoking tobacco (23.42%), followed by dyslipidemia (13.92%). Functional signs were dominated by angina 62% followed by dyspnea 25.3%. Persistent ST-segment elevation on electrocardiogram was present in 76.4%. Left ventricular systolic dysfunction was present in 26.5%. Time to first medical contact was more than 12 hours in 62.7% of cases. Radial approach was adopted in 94% of cases. Coronary angiography was pathological in 85% (n = 51) of cases. Lesions were single-vessel disease in 47.1% and culprit artery was anterior interventricular in 51% of cases. Dual anti-platelet aggregation was aspirin and ticagrelor in 91.8% of cases. Angioplasty was performed in all patients who had significant abnormalities at coronary angiography. In-hospital mortality was 3.9%. Conclusion: Acute coronary syndromes exist in young Africans with a male predominance. Main cardiovascular risk factor is smoking tobacco. Coronary lesions are single vessel disease in the majority of case. Most of patients meet medical team after 12 hours. Time to first medical contact is a main challenge in our country.

Implications of Elevated Serum Cortisol in the Onset of Postoperative Delirium Following Off-Pump Coronary Artery Bypass Grafting: Insights from a Bangladesh-Based Single Center Experience

Background: Following coronary artery bypass grafting (CABG), delirium emerges as a prevalent complication. This study aimed to assess the correlation between elevated serum cortisol levels and the occurrence of postoperative delirium subsequent to off-pump CABG. Methods: Conducted in the Department of Cardiac Surgery at BSMMU from October 2020 to September 2022, this comparative cross-sectional study included a total of 44 participants. Subjects, meeting specific criteria, were purposefully assigned to two groups based on off-pump CABG. Group A (n = 22) consisted of patients with normal serum cortisol levels, while Group B (n = 22) comprised individuals with high serum cortisol levels on the first postoperative day. Delirium onset was assessed at the bedside in the ICU on the 1st, 2nd, 3rd, 4th, and 5th postoperative days using standard tools, namely the Richmond Agitation Sedation score (RASS) and The Confusion Assessment Method (CAM-ICU). Data were collected based on the presence or absence of delirium. Statistical analysis utilized SPSS version 26.0, employing an independent Student’s t-test for continuous data and chi-square and Fischer’s exact test for categorical data. A p-value ≤ 0.05 was considered statistically significant. Results: Group-A had a mean age of 54.50 ± 17.97, and Group-B had a mean age of 55.22 ± 15.45, both with a male predominance (81.81% and 86.36% respectively). The mean serum cortisol level was significantly higher in Group B (829.71 ± vs. 389.98 ± 68.77). Postoperative delirium occurred in 27.3% of Group B patients, statistically significant compared to the 4.5% in Group A. However, patients in Group B who developed delirium experienced significantly longer postoperative ICU and hospital stays (79.29 ± 12.27 vs. 11.44 ± 2.85, p ≤ 0.05). There was one mortality in Group B, which was statistically not significant. Conclusion: This study observed a significant association between elevated serum cortisol levels in the postoperative period and the occurrence of postoperative delirium after off-pump coronary artery bypass grafting.

Effect of Cardioplegia for Myocardial Protection in Pediatric Cardiac Surgery:A Network Meta-Analysis

Cardioplegia has been widely used to reduce myocardial injury during pediatric cardiac surgery;however,which cardioplegia solution has the best protective effect has not been established.Thus,we compared the myocardial protective effects of different cardioplegia solutions used in pediatric cardiac surgery.Seven databases were searched to identify the relevant randomized controlled trials.A network meta-analysis with a Bayesian framework was conducted.The outcomes included the following biochemical and clinical outcomes:serum concentrations of the creatine kinase-myocardial band at 6 h postoperatively;cardiac troponin I(cTnI)at 4,12,and 24 h postoperatively;spontaneous beating after declamping;postoperative arrhythmias;inotropic support percentage and duration;mechanical ventilation hours;intensive care unit stay in days;hospital stay in days;and mortality.The group treated with cold crystalloid cardioplegia(cCCP)was chosen as the control group.The 22 studies involved 1529 patients.Six types of cardioplegia solutions were described in these studies,including cold blood cardioplegia,cCCP,del Nido,histidine-tryptophan-ketoglutarate(HTK),terminal warm blood cardioplegia,and warm blood cardioplegia(wBCP).The serum concentrations of the 24-h cTnI with wBCP(MD=−2.52,95%CI:−4.74 to−0.27)was significantly lower than cCCP.The serum concentrations of the 24-h cTnI with HTK(MD=4.91,95%CI:2.84–7.24)was significantly higher than cCCP.There was no significant difference in other biochemical and clinical outcomes when compared to cCCP.In conclusion,wBCP may have a superior myocardial protective effect with lower 24-h cTnI levels postoperatively and similar clinical outcomes after pediatric cardiac surgery.

Replacement Therapy for Hemophilia Patients Undergoing Cardiac Surgery: Report of Three Cases

Hemophilia is an X-linked recessive inherited bleeding disorder.Despite the improved treatment in recent years with the advent of replacement therapies,the progression of atherosclerosis is not slowed down after the reduction of clotting factors in hemophilia.As life expectancy increases,more hemophilia patients will suffer from age-related cardiovascular diseases.Since cardiac surgery needs heparinization and cardiopulmonary bypass(CPB),it is extremely challenging to balance hemostasis and coagulation in patients with hemophilia.Here we report three cases of hemophilia patients who underwent cardiac surgery successfully.

Unusual treatment of postoperative bleeding after cardiac surgery

A young patient was presented to the emergency department with chest pain and palpitations. A transthoracic echocardiogram showed a right atrial mass. Coronary angiography showed a right coronary artery with collateral circulation to a large mass. The tumor could only be partially resected and the patient experienced persistent postoperative bleeding. We performed a new right coronary artery angiography which showed an important free extravasation of contrast into the pericardium through the collateral circulation. Using covered stents, the bleeding was controlled. The pathological examination performed later revealed a primary cardiac angiosarcoma. After asymptom-free survival of 14 months the patient presented bone metastases.

Evaluation of 100 Cases of Mortality after Cardiac Surgery: A Single-Center Experience in Bangladesh

Background: Vigilance ensures safety in cardiac surgery. Performance in cardiac surgery is often measured by short-term mortality. Several risk factors like advanced age, female gender, higher body mass index, decreased left ventricular function, emergent, and redo operations have appeared recurrently as poor prognostic variables. Evaluation of postoperative mortality is crucial to find loopholes to provide proper care and reduce preventable mortality after cardiac surgery in developing countries with limited infrastructures and resources. Methods: This is a retrospective study conducted in the Department of Cardiac Surgery, Bangabandhu Sheikh Mujib Medical University. Perioperative data of 100 cases of mortality after cardiac surgery performed from 1 January 2014 to 30 May 2018 were collected from the university medical record. The data on age, gender, body mass index, preoperative investigations, diagnoses, types of operations, details of cardiopulmonary bypass, and postoperative period of the study populations were evaluated. Results: During the study period, about 1627 cases of cardiac surgery were done with an overall mortality rate of 6.15%. The mean age was 41.05 ± 20.19 (0 - 68) years, and 66% of patients were male. Preoperative ejection fraction (EF) of the study population was an average 56.63% ± 11.85%;9% of the patients had EF < 40%. Off-pump coronary artery bypass (32.27%) was the most commonly performed surgery followed by mitral valve replacement (24.28%). On-pump cardiac surgery was done among 65% of the study population with a mean cross-clamp time and bypass time of 32.56 ± 11.55 minutes and 80.57 ± 18.09 minutes, respectively. Most of the mortality was found in the first two weeks after surgery. Conclusion: Mortality after cardiac surgery is multifactorial. A large-scale prospective study with comparative groups is required to find out preventable measures of mortality after cardiac surgery which will improve the quality of services provided to the patients in developing countries.

A Comparative Study on Safety and Efficacy of Caudal, Thoracic Epidural and Intra Venous Analgesia in Paediatric Cardiac Surgery: A Double Blind Randomised Trial

Introduction:Regional anaesthesia combined with general anaesthesia reduces stress response to surgery, duration of ventilation, intensive care unit (ICU) stay and promotes early recovery. Studies on thoracic epidural, caudal analgesia along with general anaesthesia (GA) in paediatric cardiac surgery are limited hence we aimed to compare efficacy and safety of caudal, thoracic epidural and intravenous analgesia in paediatric cardiac surgery. Methodology: This study was conducted in the Department of Anaesthesiology in a tertiary care teaching hospital in southern India from February 2019 to December 2019. 90 children were randomised into group A, group B, group C. Children in group A received caudal analgesia along with GA. Group B children received thoracic epidural along with GA. Group C patients received intravenous analgesia along with GA. Rescue analgesia 1 mcg/kg fentanyl given in all 3 groups if pain score is more than 4. Primary outcome assessed was post-op pain scores. Secondary outcome assessed was duration of ventilation, duration of intensive care unit stay. Results: All patients were comparable in terms of age, sex, weight, mean RACHS score, baseline heart rate and blood pressure. Pain scores were significantly lower in thoracic epidural group compared to other two grou ps. Duration of ventilation was lower in thoracic epidural group (91.17± 43.85) minutes and caudal (199.6 ± 723.59) minutes compared to intravenous analgesia groups (436.37 ± 705.51) minutes. Duration of ICU stay was significantly low in thoracic epidural group (2.73 ± 0.69) days compared to caudal (3.7 ± 2.8) and intravenous analgesia groups (4.33 ± 0.920). We didn’t have any complications like hematoma, transient or permanent neurological sequelae in regional anesthesia groups. Conclusion: Regional anaesthesia along with general anaesthesia was more effective in pain relief than intravenous analgesia with general anaesthesia in paediatric cardiac surgery.

Construction of A Prediction Model for Atrial Fibrillation in Patients with Dilated Cardiomyopathy and Heart Failure

Dilated cardiomyopathy(DCM)is a common myocardial disease characterized by enlargement of the heart cavity and decreased systolic function,often leading to heart failure(HF)and arrhythmia.The occurrence of atrial fibrillation(AF)is closely related to the progression and prognosis of the disease.In recent years,with the advancement of medical imaging and biomarkers,models for predicting the occurrence of AF in DCM patients have gradually become a research hotspot.This article aims to review the current situation of AF in DCM patients and explore the importance and possible methods of constructing predictive models to provide reference for clinical prevention and treatment.We comprehensively analyzed the risk factors for AF in DCM patients from epidemiological data,pathophysiological mechanisms,clinical and laboratory indicators,electrocardiogram and imaging parameters,and biomarkers,and evaluated the effectiveness of existing predictive models.Through analysis of existing literature and research,this article proposes a predictive model that integrates multiple parameters to improve the accuracy of predicting AF in DCM patients and provide a scientific basis for personalized treatment.

Intraoperative vs 24-Hour Administration of Cefamandole to Prevent Deep Sternal Wound Infection and Endocarditis after Adult Cardiac Surgery

Background and Objectives: Duration of antibiotic prophylaxis for cardiac surgery is still debated and controversial. International guidelines are vague: French guidelines recommend an intraoperative administration, while the Society of Thoracic Surgeons’ guidelines suggest that optimal postoperative prophylactic antibiotics be given for 48 hours or less. Very few studies have compared the same antibiotic with 2 different administration durations. The study was designed to compare the efficacy of 24-hour administration of cefamandole vs intraoperative cefamandole to prevent deep sternal wound infection and endocarditis after cardiac surgery. Methods: This retrospective and observational study compared the rates of severe surgical site infections (deep sternal wound infection, endocarditis) after cardiac surgery between period 1, 01/01/2008-31/08/2008, with 24-hour administration of cefamandole, and period 2, 01/09/2008-30/04/2009 with intraoperative cefamandole. Results: Among 933 patients, 14 patients (1.5%) developed surgical site infection during the 16-month study: 1.3% during the first period and 1.7% during the second (ns). The populations (470 patients in period 1 and 463 in period 2) were homogeneous and comparable for pre-, intra- and postoperative characteristics. Surgical site infection characteristics (pathogens involved, time to diagnosis) and consequences (longer hospital stay, outcomes) were comparable in the 2 groups. Conclusions: Intraoperative cefamandole was as safe as its 24-hour administration to prevent deep sternal wound infection and endocarditis after adult cardiac surgery.

Heart rate variability： a new tool to predict complications in adult cardiac surgery

心率可变性(HRV ) 指在连续心跳之间的变化，它取决于自治神经系统的同情、副交感的分支的连续调整。HRV 被显示了作为在心肌的梗塞和糖尿病的神经病的早警告症状以后的风险的一个预言者有效，并且在心病学，背景是认出是为在医院承认以后并且在分泌物以后的风险层化的一个有用工具的现在。最近的证据建议 HRV 分析可能甚至在经历心脏的外科，和现在的评论的病人预言复杂并发症在当前的临床的实践为 HRV 使用在成年心脏的外科和观点总结 HRV 分析的重要性。尽管未来在 HRV 能在成年心脏的外科被包括进每日的临床的实践以前，更大的研究被保证， HRV 是可能在早手术后的阶段并且在医院停留期间检测自治不稳定性的一个新奇工具，因此预言或迅速诊断许多手术后的复杂并发症。

Sonographic muscle mass assessment in patients after cardiac surgery

BACKGROUND Patients undergoing cardiac surgery particularly those with comorbidities and frailty,experience frequently higher rates of post-operative morbidity,mortality and prolonged hospital length of stay.Muscle mass wasting seems to play important role in prolonged mechanical ventilation(MV)and consequently in intensive care unit(ICU)and hospital stay.AIM To investigate the clinical value of skeletal muscle mass assessed by ultrasound early after cardiac surgery in terms of duration of MV and ICU length of stay.METHODS In this observational study,we enrolled consecutively all patients,following their admission in the Cardiac Surgery ICU within 24 h of cardiac surgery.Bedside ultrasound scans,for the assessment of quadriceps muscle thickness,were performed at baseline and every 48 h for seven days or until ICU discharge.Muscle strength was also evaluated in parallel,using the Medical Research Council(MRC)scale.RESULTS Of the total 221 patients enrolled,ultrasound scans and muscle strength assessment were finally performed in 165 patients(patients excluded if ICU stay<24 h).The muscle thickness of rectus femoris(RF),was slightly decreased by 2.2%[(95%confidence interval(CI):-0.21 to 0.15),n=9;P=0.729]and the combined muscle thickness of the vastus intermedius(VI)and RF decreased by 3.5%[(95%CI:-0.4 to 0.22),n=9;P=0.530].Patients whose combined VI and RF muscle thickness was below the recorded median values(2.5 cm)on day 1(n=80),stayed longer in the ICU(47±74 h vs 28±45 h,P=0.02)and remained mechanically ventilated more(17±9 h vs 14±9 h,P=0.05).Moreover,patients with MRC score≤48 on day 3(n=7),required prolonged MV support compared to patients with MRC score≥49(n=33),(44±14 h vs 19±9 h,P=0.006)and had a longer duration of extracorporeal circulation was(159±91 min vs 112±71 min,P=0.025).CONCLUSION Skeletal quadriceps muscle thickness assessed by ultrasound shows a trend to a decrease in patients after cardiac surgery post-ICU admission and is associated with prolonged duration of MV and ICU length of stay.

Effect of L-carnitine on Cardiomyocyte Apoptosis and Cardiac Function in Patients Undergoing Heart Valve Replacement Operation

Summary： The effects of L-carnitine, as an ingredient of cardioplegia solution, on cardiac function and cardiomyocyte apoptosis in patients undergoing heart valve replacement operation were investigated. Twenty-three cases undergoing heart valve replacement with cardiopulmonary bypass （CPB） were randomly allocated into two groups： L-carnitine group （n=12, 12 g/L L-carnitine was put in the ST. Thomas cardioplegia） and control group （n=11, identical to the L-carnitine group except that normal saline was administered instead of L-carnitine）. Serum cardial troponin I （cTnI） levels, the left ventricular ejection fraction （LVEF）, and cardiac index （CI） were measured perioperatively. A bit of myocardial tissue obtained from right atria was taken before CPB and by the end of intracardiac procedure to undergo electron microscopy examination and estimate apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling （TUNEL）. From the end of CPB to 3 days after operation, the serum levels of cTnI in the L-carnitine group was significantly lower than that in the control group （P〈0.05）. Heart color ultrasonogram showed that the CI index and LVEF at 7th day postoperatively in the L-carnitine group were significantly higher than in the control group （P〈0.05）. Compared to the control group, L-carnitine significantly alleviated the morphologic changes of cardiac muscle cells （electron microscopy examination） and decreased the amounts of apoptotic cardiac muscle cells （TUNEL）. Furthermore, the dosage of vasoactive drugs used after operation was significantly less in the L-carnitine group （P〈0.01）. It was concluded that L-carnitine cardioplegia solution could improve cardiac function in patients undergoing heart valve replacement operation and alleviate CPB-mediated apoptosis of cardiac muscle cells.