Understanding heart failure in the elderly with respect to diastolic dysfunction and role for natriuretic peptides

The current issue of the Journal of Geriatric Cardiology contains an interesting paper by Dr. Yixin Song and colleagues raising important issues in the diagnosis and management of heart failure in elderly patients. Readers of this journal are in all likelihood aware that the epidemic of heart failure is of great impact medically and economically worldwide.

Left Ventricular Diastolic Dysfunction and Silent Myocardial Ischemia amongst Asymptomatic Type 2 Diabetic Patients in Two Referral Hospitals in Cameroon

Background: Cardiovascular events, the leading cause of death among diabetic patients, are usually under-diagnosed due to subclinical presentation. Methods: We conducted a cross-sectional study from March-2019 to September-2020, in two reference hospitals in Yaoundé, Cameroon, to assess the prevalence of asymptomatic Left Ventricular Diastolic Dysfunction (LVDD) and Silent Myocardial Infarction (SMI) and potentially associated factors. Results: Out of 95 participants (mean age ± SD: 43 ± 7 years;M/F sex-ratio 1.6), 22 (23.1%;95% CI: 15.8% - 32.6%) had LVDD and fewer (n = 13, 13.6%;95% CI: 8.2% - 22.0%) had SMI, p = 0.86. Though not statistically significant, patients with ≥5 years diabetes duration, as well as patients with HbA1C ≥ 7.5% had two-fold increased risk of LVDD (p = 0.22 and p = 0.15 respectively). LVDD was significantly higher in patients with SMI (29% vs 6.3%, p Conclusion: The significant presence of asymptomatic cardiovascular manifestations in this population entails mandatory preventive screening, especially, in patients with long standing diabetes and poor glycemic control, to allow timely detection and management.

Left atrial minimum volume by real-time three-dimensional echocardiography as an indicator of diastolic dysfunction

Background Left atrial （LA） maximum volume is becoming a prognostic biomarker for left ventricular （LV） diastolic dysfunction. However, we assessed LV diastolic function by measuring LA phasic volumes using real-time threedimensional echocardiography （RT3DE） in patients with stable coronary artery disease （CAD）. Methods Sixty-five stable CAD patients with normal LV ejection fraction （LVEF） were divided into three groups according to degree of coronary stenosis： control （n=15） with 〈50% stenosis as control group, mildS （n=25） with mild stenosis （50%- 70%） and severeS （n=25） with 〉70% stenosis. LA phasic volumes and function were evaluated and compared using RT3DE and two dimensional echocardiography （2DE）. N-terminal pro-B-type natriuretic peptide （NT-proBNP） levels were examined. The correlations of RT3DE-derived parameters with other conventional indices were analyzed. Results Significant correlations between RT3DE and 2DE for LA volume measurements were： control, r=0.93; mildS, 1=0.94; severeS, r=0.90 （all P 〈0.05）. Patients with severe coronary stenosis presented higher NT-proBNP level, indices of LA minimum volume and volume before atrial contraction, but lower LA total emptying fraction （LAEF） and LAEFpass^ve. Significant correlations of RT3DE derived LA volume indices with E/E＇ （r=0.695） and NF-proBNP （r=0.630） level were found. Conclusions RT3DE derived, LA indices correlate well with NT-proBNP level and may be superior to 2DE measurements for the evaluation of LV diastolic dysfunction. Enlargement of LA minimum volume in stable CAD patients without systolic dysfunction appears earlier and may be better correlated with LV diastolic function than that of LA maximum volume.

Effects of exercise training on diastolic and systolic dysfunction in patients with chronic heart failure

BACKGROUND Chronic heart failure(CHF)is a complex syndrome characterized by a progressive reduction of the left ventricular(LV)contractility,low exercise tolerance,and increased mortality and morbidity.Diastolic dysfunction(DD)of the LV,is a keystone in the pathophysiology of CHF and plays a major role in the progression of most cardiac diseases.Also,it is well estimated that exercise training induces several beneficial effects on patients with CHF.AIM To evaluate the impact of a cardiac rehabilitation program on the DD and LV ejection fraction(EF)in patients with CHF.METHODS Thirty-two stable patients with CHF(age:56±10 years,EF:32%±8%,88%men)participated in an exercise rehabilitation program.They were randomly assigned to aerobic exercise(AER)or combined aerobic and strength training(COM),based on age and peak oxygen uptake,as stratified randomization criteria.Before and after the program,they underwent a symptom-limited maximal cardiopulmonary exercise testing(CPET)and serial echocardiography evaluation to evaluate peak oxygen uptake(VO2peak),peak workload(Wpeak),DD grade,right ventricular systolic pressure(RVSP),and EF.RESULTS The whole cohort improved VO2peak,and Wpeak,as well as DD grade(P<0.05).Overall,9 patients(28.1%)improved DD grade,while 23(71.9%)remained at the same DD grade;this was a significant difference,considering DD grade at baseline(P<0.05).In addition,the whole cohort improved RVSP and EF(P<0.05).Not any between-group differences were observed in the variables assessed(P>0.05).CONCLUSION Exercise rehabilitation improves indices of diastolic and systolic dysfunction.Exercise protocol was not observed to affect outcomes.These results need to be further investigated in larger samples.

THE EFFECT OF LEFT VENTRICULAR DIASTOLIC DYSFUNCTION ON THE PATHOGENESIS OF ANGINA DECUBITUS

Objective. To investigate the effect of left ventricular diastolic dysfunction on the pathogenesis of angina decubitus (AD). Methods. The study population consisted of three groups: 20 individuals without cardiovascular disease were studied as group Ⅰ.Group Ⅱ included 20 patents with coronary artery disease and without AD. Thirty-one patients with AD and ejection fraction(EF)>50% were studied as group Ⅲ. Group Ⅱ and Ⅲ were matched for age, EF and extent of coronary artery disease. Results. Left ventriculography (LVG) showed that left ventricular (LV) first 1/3 filling fraction(1/3FF) was significantly lower in group Ⅲ than in group Ⅱ and Ⅰ(both P<0001),but LV late 1/3 FF was much higher in group Ⅲ than in group Ⅱ and Ⅰ(P<005, P<001). Left ventricular end-diastolic pressure(LVEDP)was markedly increased before and after LVG in group Ⅱ and Ⅲ as compared with group Ⅰ (both P<005, both P<0001). The difference of LVEDP caused by left atrial contraction (left atrial contraction pressure difference, LACPD)before and after LVG was much higher in group Ⅲ than in group Ⅰ ( P<001, P<0001). Howevere,there were significant differences in LVEDP and in LACPD between before and after LVG only in group Ⅲ (both P<001). Conclusion. The patients with AD have LV diastolic dysfunction, which may be closely related to the pathogenesis of angina decubitus.

Heart failure with preserved ejection fraction and the first law of thermodynamics

In heart failure with preserved ejection fraction,significant left ventricular diastolic abnormalities are present,despite a normal systolic ejection fraction.This article will consider whether this is consistent with the law of conservation of energy,also know as the first law of thermodynamics.

Assessment and impact of diastolic function by echocardiography in elderly patients

Doppler echocardiography is the gold standard for assessment of diastolic dysfunction, which is increasingly recognised as a cause of heart failure, especially in the elderly. Using a combination of Doppler echocardiography techniques, it is possible to identify grades of dia- stolic dysftmction, estimate left ventricular filling pressures and establish the chronicity of diastolic dysfunction. These physiologi- cally-derived measures have been widely validated against invasive measurements of left heart pressures and have been shown to be prog- nostically valuable in a wide range of clinical settings. This review explores the mechanisms, and approaches to the assessment of diastolic dysfunction in the elderly. The challenge for clinicians is to identify pathophysiological changes from those associated with normal ageing. When used in combination, and taking age into account, Doppler echocardiographic parameters are helpful in the assessment of dyspnoea in older patients and provide prognostic insights.

Cirrhotic cardiomyopathy:A cardiologist's perspective

Cardiac dysfunction is frequently observed in patients with cirrhosis, and has long been linked to the direct toxic effect of alcohol. Cirrhotic cardiomyopathy(CCM) has recently been identified as an entity regardless of the cirrhosis etiology. Increased cardiac output due to hyperdynamic circulation is a pathophysiological hallmark of the disease. The underlying mechanisms involved in pathogenesis of CCM are complex and involve various neurohumoral and cellular pathways, including the impaired β-receptor and calcium signaling, altered cardiomyocyte membrane physiology, elevated sympathetic nervous tone and increased activity of vasodilatory pathways predominantly through the actions of nitric oxide, carbon monoxide and endocannabinoids. The main clinical features of CCM include attenuated systolic contractility in response to physiologic or pharmacologic strain, diastolic dysfunction, electrical conductance abnormalities and chronotropic incompetence. Particularly the diastolic dysfunction with impaired ventricularrelaxation and ventricular filling is a prominent feature of CCM.The underlying mechanism of diastolic dysfunction in cirrhosis is likely due to the increased myocardial wall stiffness caused by myocardial hypertrophy,fibrosis and subendothelial edema,subsequently resulting in high filling pressures of the left ventricle and atrium.Currently,no specific treatment exists for CCM.The liver transplantation is the only established effective therapy for patients with end-stage liver disease and associated cardiac failure.Liver transplantation has been shown to reverse systolic and diastolic dysfunction and the prolonged QT interval after transplantation.Here,we review the pathophysiological basis and clinical features of cirrhotic cardiomyopathy,and discuss currently available limited therapeutic options.

Is diabetic cardiomyopathy a specific entity?

Diabetes mellitus(DM) is characterised by hyperglycemia, insulin resistance and metabolic dysregulation leading to diastolic and systolic dysfunction in diabetes. In this review, the pathogenetic and pathomorphological changes leading to diastolic and systolic dysfunction in diabetes are discussed. Changes in metabolic signalling pathways, mediators and effectors contribute to the pathogenesis of cardiac dysfunction in DM called diabetic cardiomyopathy(DC). Echocardiographic studies report on the association between DM and the presence of cardiac hypertrophy and myocardial stiffness that lead to diastolic dysfunction. More recently reported echocardiographic studies with more sensitive techniques, such as strain analysis, also observed systolic dysfunction as an early marker of DC. Depression of systolic and diastolic function is continuum and the line of separation is artificial. To conclude, according to current knowledge, DC is expected to be a common single phenotype that is caused by different pathogenetic and pathomorphological changes leading to diastolic and systolic dysfunction in diabetes.

Investigation of Myocardial Stunning after Cardiopulmonary Resuscitation in Pigs

Objective To investigate cardiac function and myocardial perfusion during 48 h after cardiopulmonary resuscitation （CPR）, further to test myocardial stunning and seek indicators for long‐term survival after CPR. Methods After 4 min of untreated ventricular fibrillation, fifteen anesthetized pigs were studied at baseline and 2 h, 4 h, 24 h, and 48 h after restoration of spontaneous circulation （ROSC）. Hemodynamic data, echocardiography and gated‐single photon emission computed tomography myocardial perfusion images were carried out. Results Mean arterial pressure （MAP）, coronary perfusion pressure （CPP） and cardiac troponin I （CTNI） showed significant differences between eventual survival animals and non‐survival animals at 4 h after ROSC （109.2±10.7 mmHg vs. 94.8±12.3 mmHg, P=0.048; 100.8±6.9 mmHg vs. 84.4±12.6 mmHg, P=0.011; 1.60±0.13 ug/L vs. 1.75±0.10 ug/L, P=0.046）. Mitral valve early‐to‐late diastolic peak velocity ratio, mitral valve deceleration time recovered 24 h; ejection faction and the summed rest score recovered 48 h after ROSC. Conclusion Cardiac systolic and early active relaxation dysfunctions were reversible within survival animals; cardiac stunning might be potentially adaptive and protective after CPR. The recovery of MAP, CPP, and CTNI could be the indicators for long‐term survival after CPR.

Cardiovascular risk after orthotopic liver transplantation, a review of the literature and preliminary results of a prospective study

Improved surgical techniques and greater efficacy of new anti-rejection drugs have significantly improved the survival of patients undergoing orthotopic liver transplantation(OLT). This has led to an increased incidence of metabolic disorders as well as cardiovascular and cerebrovascular diseases as causes of morbidity and mortality in OLT patients. In the last decade, several studies have examined which predisposing factors lead to increased cardiovascular risk(i.e., age, ethnicity, diabetes, NASH, atrial fibrillation, and some echocardiographic parameters) as well as which factors after OLT(i.e., weight gain, metabolic syndrome, immunosuppressive therapy, and renal failure) are linked to increased cardiovascular mortality. However, currently, there are no available data that evaluate the development of atherosclerotic damage after OLT. The awareness of high cardiovascular risk after OLT has not only lead to the definition of new but generally not accepted screening of high risk patients before transplantation, but also to the need for careful patient follow up and treatment to control metabolic and cardiovascular pathologies after transplant. Prospective studies are needed to better define the predisposing factors for recurrence and de novo occurrence of metabolic alterations responsible for cardiovascular damage after OLT. Moreover, such studies will help to identify the timing of disease progression and damage,which in turn may help to prevent morbidity and mortality for cardiovascular diseases. Our preliminary results show early occurrence of atherosclerotic damage, which is already present a few weeks following OLT, suggesting that specific, patient-tailored therapies should be started immediately post OLT.

Risks of incident heart failure with preserved ejection fraction in Chinese patients hospitalized for cardiovascular diseases

Background Endogenous aldehyde damages DNA and potentiates an ageing phenotype. The aldehyde dehydrogenase 2(ALDH2) rs671 polymorphism has a prevalence of 30%–50% in Asian populations. In this study, we aimed to analyze risk factors contributing to the development of heart failure with preserved ejection fraction(HFpEF) along with the genetic exposure in Chinese patients hospitalized with cardiovascular diseases(CVD). Methods From July 2017 to October 2018, a total of 770 consecutive Chinese patients with normal left ventricular ejection fractions(LVEF) and established CVD(hypertension, coronary heart diseases, or diabetes) were enrolled in this prospective cross-sectional study. HFpEF was defined by the presence of at least one of symptom(dyspnoea and fatigue) or sign(rales and ankle swelling) related to heart failure;N-terminal pro-B-Type natriuretic peptide(NT pro-BNP ≥ 280 pg/mL);LVEF ≥ 50%;and at least one criterion related to elevated ventricular filling pressure or diastolic dysfunction(left atrial diameter > 40 mm, E/E’ ≥ 13, E’/A’ < 1 or concurrent atrial fibrillation). Logistic regression was performed to yield adjusted odds ratios(ORs) for HFp EF incidence associated with traditional and/or genetic exposures. Results Finally, among 770 patients with CVD, 92(11.9%) patients were classified into the HFpEF group according to the diagnostic criteria. The mean age of the participants was 67 ± 12 years, and 278(36.1%) patients were females. A total of 303(39.4%) patients were ALDH2*2 variant carriers. In the univariate analysis, eight exposures were found to be associated with HFpEF: atrial fibrillation, ALDH2*2 variants, hypertension, age, anaemia, smoking, alcohol consumption and sex. Multivariable logistic regression showed that 4 ‘A’ variables(atrial fibrillation, ALDH2*2 variants, age and anaemia) were significantly associated with an increased risk of HFpEF. Atrial fibrillation was associated with a 3.8-fold increased HFpEF risk(95% CI: 2.21–6.61, P < 0.001), and the other three exposures associated with increased HFpEF risk were the ALDH2*2 variant(OR = 2.41, 95% CI: 1.49–3.87, P < 0.001), age(OR = 2.14, 95% CI: 1.27–3.60, P = 0.004), and anaemia(OR = 1.79, 95% CI: 1.05–3.03, P = 0.032). These four variables predicted HFpEF incidence in Chinese CVD patients(C-statistic = 0.745, 95% CI: 0.691–0.800, P < 0.001). Conclusions 4 A traits(atrial fibrillation, ALDH2*2 variants, age and anaemia) were associated with an increased risk of HFpEF in Chinese CVD patients. Our results provide potential clues to the aetiology, pathophysiology and therapeutic targets of HFpEF.

Heart failure in older adults：embracing complexity

Heart failure （HF）, particularly in the setting of preserved systolic function, disproportionately afflicts older individu- als and results in significant morbidity, mortality, and health care costs. In the United States, among the Medicare population （age 〉 65 years）, HF is among the leading cause of hospital admissions. Optimal care for older adults with HF requires knowledge of age-related physiologic changes, complex multi-organ, multi-dimensional syndromes, interdisciplinary teamwork and palliative/end of life care.

Left atrial physiology and pathophysiology:Role of deformation imaging

The left atrium(LA) acts as a modulator of left ventricular(LV) filling. Although there is considerable evidence to support the use of LA maximum and minimum volumes for disease prediction,theoretical considerations and a growing body of literature suggest to focus on the quantification of the three basic LA functions:(1) Reservoir function:collection of pulmonary venous return during LV systole;(2) Conduit function:passage of blood to the left ventricle during early LV diastole; and(3) Contractile booster pump function(augmentation of ventricular filling during late LV diastole. Tremendous advances in our ability to non-invasively characterize all three elements of atrial function include speckle tracking echocardiography(STE),and more recently cardiovascular magnetic resonance myocardial feature tracking(CMR-FT). Corresponding imaging biomarkers are increasingly recognized to have incremental roles in determining prognosis and risk stratification in cardiac dysfunction of different origins. The current editorial introduces the role of STE and CMR-FT for the functional assessment of LA deformation as determined by strain and strain rate imaging and provides an outlook of how this exciting field may develop in the future.

Serum uric acid in patients with acute ST-elevation myocardial infarction

BACKGROUND:Few studies investigated serum uric acid levels in patients with acute STelevation myocardial infarction(STEMI).The study was to assess the clinical value of serum uric acid levels in patients with acute ST-elevation myocardial infarction(STEMI).METHODS:Totally 502 consecutive patients with STEMI were retrospectively studied from January 2005 to December 2010.The level of serum lipid,echocardiographic data and in-hospital major adverse cardiovascular events(MACE) in patients with hyperuricemia(n=119) were compared with those in patients without hyperuricemia(n=383).The relationship between the level of serum uric acid and the degree of diseased coronary artery was analyzed.All data were analyzed with SPSS version 17.0 software for Student's t test,the Chi-square test and Pearson's correlation coefficient analysis.RESULTS:Serum uric acid level was positively correlated with serum triglyceride level.Hyperlipidemia was more common in hyperuricemia patients than in non-hyperuricemia patients(43.7%vs.33.7%,P=0.047),and serum triglyceride level was significantly higher in hyperuricemia patients(2.11±1.24 vs.1.78±1.38,P=0.014).But no significant association was observed between serum uric acid level and one or more diseased vessels(P>0.05).Left ventricular end-diastolic diameter(LVEDd) was larger in hyperuricemia patients than in non-hyperuricemia patients(53.52±6.19 vs.52.18±4.89,P=0.041).The higher rate of left systolic dysfunction and diastolic dysfunction was discovered in hyperuricemia patients(36.4%vs.15.1%,P<0.001;68.2%vs.55.8%,P=0.023).Also,hyperuricemia patients were more likely to have in-hospital MACE(P<0.05).CONCLUSIONS:Serum uric acid level is positively correlated with serum triglyceride level,but not with the severity of coronary artery disease.Hyperuricemia patients with STEMI tend to have a higher rate of left systolic dysfunction and diastolic dysfunction and more likely to have more in-hospital MACE.

Relationship between exercise induced elevation of left ventricular filling pressure and exercise intolerance in patients with atrial fibrillation

Background Elevated left ventricular filling pressure （LVFP） is an important cause of exercise intolerance in patients with atrial fib- dilation （AF）. Exercise stress echocardiography could assess LVFP during exercise. The objective of this study was to investigate the relationship between exercise induced elevation of LVFP and exercise capacity in patients with AF. Methods This study included 145 con- secutive patients （81 men and 64 women; mean age 65.5 ± 8.0 years） with persistent non-valvular AF and normal left ventricular systolic function （left ventdcular ejection fraction 〉 50%）. All patients underwent a symptom-limited cardiopulmonary exercise test （CPET）. Doppler echocardiography was performed both at rest and immediately after exercise. Five consecutive measurements of early diastolic mitral inflow velocity （E） and early diastolic mitral annular velocity （e＇） were taken and averaged. E/e＇ ratio was calculated. Elevated LVFP was defined as E/e＇ 〉 9, and patients with elevated LVFP at rest were excluded. Results Patients were classified into two groups according to LVFP estimated by E/e＇ ratio after exercise： 39 （26.9%） with elevated LVFP after exercise and 106 （73.1%） with normal LVFP. As compared with patients with normal LVFP, the ones with elevated LVFP after exercise had significantly lower peak oxygen uptake （VO2 peak） （21.7 ± 2.3 vs. 26.4 ± 3.8 mL/min per kilogram, P 〈 0.001）, lower anaerobic threshold （19.9 ± 2.5 vs. 26.0± 4.0 mL/min per kilogram, P 〈 0.001）, and shorter exercise time duration （6.2± 0.8 vs. 7.0 ±1.3 min, P 〈 0.001）. Multivariate analysis showed that age, gender and E/e＇ after exercise were significantly correlated with VO2peak. Conclusion Elevated LVFP estimated by E/e＇ ratio after exercise is independently associated with reduced exercise capacity in AF patients.

RE-EVALUATION OF THE MECHANISM AND TREATMENT OF ANGINA DECUBITUS

patients with angina decubitus (AD) were studied during hospitalization. These patients were found to have severe coronary artery obstructive lesions and an increase of myocardial oxygen consumption (MOC) before the onset to AD, indicating that AD belongs to the category of effort angina.18 patients were investigated by continuous hemodynamic monitoring. Three patients had significant increase in pulmonary artery diastolic pressure (PADP) before the onset. In the other 15 patients. PADP increased slightly in 12 and remained unchanged in 3 cases before the onset. Left ventriculography showed ejection fraction (EF)>45% in 25 of the 27 patients. These results indicate that left ventricular (LV) systolic dysfunction is not a major factor in the Pathogenesis of AD. The patients with LVEDP>12 mmHg constituted 60% of 25 patients with EF>45%, suggesting that these patients had ohvious LV diastolic dysfunction, which may be the major factor in the pathogenesis of AD.According to the results of our treatment, beta blockers may be used as the major form of tteatment in the patients with AD.

To ventricular assist devices or not:When is implantation of a ventricular assist device appropriate in advanced ambulatory heart failure?

Advanced heart failure has been traditionally treated via either heart transplantation,continuous inotropes,consideration for hospice and more recently via left ventricular assist devices(LVAD).Heart transplantation has been limited by organ availability and the futility of other options has thrust LVAD therapy into the mainstream of therapy for end stage heart failure.Improvements in technology and survival combined with improvements in the quality of life have made LVADs a viable option for many patients suffering from heart failure.The question of when to implant these devices in those patients with advanced,yet still ambulatory heart failure remains a controversial topic.We discuss the current state of LVAD therapy and the risk vs benefit of these devices in the treatment of heart failure.

Exercise Catheterization for Hemodynamic Evaluation of Adults with Coarctation of the Aorta

Background: Coarctation of the aorta (CoA) is associated with a generalized arteriopathy and long-term complicationsdespite repair. Data on invasive exercise hemodynamics in this population are lacking. Accordingly, wereviewed adults with CoA undergoing exercise catheterization to assess 1. hemodynamic profile;2. feasibilityfor assessment of CoA severity. Methods: Twenty patients undergoing exercise cardiac catheterization (12 armadduction and 8 supine cycle ergometry) at a quaternary care center between 2004 and 2021 were identified. Restingand exercise hemodynamic data were abstracted from the procedure logs. Results: Mean age was 43.6 ±12.0 years. Eleven patients (55%) had resting pulmonary arterial wedge pressure (PAWP) >15 mmHg;amongthose undergoing arterial catheterization, left ventricular end-diastolic pressure was >15 mmHg in 63%. Elevenpatients (55%) had pulmonary hypertension: 7 (35%) combined and 4 (20%) isolated post-capillary. At peak exercise,ΔPAWP/Δcardiac output (CO) ≥2 and Δmean pulmonary artery pressure/ΔCO ≥3 mmHg/l/min were foundin 7 (78%) and 6 (67%) patients, respectively;the composite of exercise PAWP ≥25 mmHg or ΔPAWP/ΔCO>2 was seen in 12 (86%). CoA peak-to-peak gradients at baseline (n = 14) and during exercise (n = 9) were 12(3–16) and 16 mmHg (9–28), respectively. Only 2 patients had an increase in CoA gradient to >20 mmHg withexercise. Conclusions: Diastolic dysfunction and pulmonary hypertension were highly prevalent, with exerciseunmasking abnormal diastolic and pulmonary vascular reserve in some individuals. Most patients failed to showsignificant increases in CoA peak-to-peak gradients with exercise. Further studies are warranted to establish thebest diagnostic method for CoA severity assessment.

Interventions of side branches in the management of left ventricular dysfunction： a study based on the virtual dual chamber of the left ventricle

For interventional cardiologists, it is very challenging to do percutaneous coronary interventions （PCI） in lesions of ihe left main, bifilrcations or of chronic total occlusion types. However, it is more challenging to demonstrate an evidence based rationale supporting the indications of PCI in these lesions. In this article, new questions are raised on the benefits and the mechanism of benefits for PCI of bifilrcations revolving large side branches such as the diagonal （DIAG）,