Sub-clinical Detection of Left Ventricular Myocardial Dysfunction in Valvular Heart Diseases: A State-of-the-Art Review in a Speckle Tracking Echocardiography and Myocardial Performance

Purpose of the state-of-the-art review: Left ventricular (LV) global longitudinal strain (GLS) is recently recognized as a more sensitive measure of LV myocardial systolic function compared with LV ejection fraction (LVEF). In addition, left ventricular GLS , myocardial performance index (MPI) and maximum rate of LV pressure rise during isovolumetric contraction (LV dP/dtmax) are more reproducible than traditional assessment of LV systolic function by two dimensional echocardiography (2DE) LVEF. These underutilized techniques can detect preclinical myocardial dysfunction in patients who are at risk of LV failure in valvular-induced heart disease . Current guidelines for diagnosis and treatment of valvular heart disease (VHD) include LVEF as one of the parameters to take into consideration in the clinical decision-making. However, a large body of evidence has shown that left ventricular GLS, MPI and LV dP/dtmax have been classically considered as a sensitive marker of LV contractility and inotropic state. In turn GLS and myocardial performance may be a better prognosticator than LVEF in aortic and mitral valve heart diseases. This timely state-of-the-art review, appraised the evidence and role of GLS, MPI and dP/dT as clinical tools in patients with aortic and mitral valve disease. Recent findings: Left ventricular GLS has been shown to be prognostic in low-flow, low-gradient severe aortic stenosis with preserved LVEF. The role of left ventricular GLS, Tei index (MPI) and maximum rate of LV pressure rise (LV dP/dtmax) in patients with aortic regurgitation and mitral valve diseases (regurgitation and stenosis) is less well established. Summary: Echocardiography is considered the primary non-invasive imaging tool for valvular heart disease assessment and the cornerstone method in diagnosing and evaluating the morphology and severity of aortic and mitral valve diseases. Currently, diagnostic-cardiac catheterization is no more recommended except in very rare cases when echocardiographic image quality is suboptimal, non-diagnostic and when the results of 2DE are discrepant with clinical data. Once clinical decision-making is based on the 2DE and three dimensional echocardiographic in assessment of the severity of mitral and aortic valve diseases, it is crucial that standards should be adopted to maintain accuracy and consistency across echocardiographic laboratories. This illustrative review article assesses left ventricular systolic function (LVEF) employing two and/or three dimensional echocardiography in comparison to GLS, MPI and LV dP/dtmax, especially applied for aortic valve (AV) and mitral valve (MV) diseases. It is noteworthy that this document only provides echocardiographic standards rather than making recommendations for clinical management. Conclusion: It is concluded that GLS, MPI and maximum rate of LV pressure rise during isovolumetric contraction (LV dP/dtmax) are recommended and more so, they should be increasingly used to identify subclinical LV myocardial dysfunction in patients with mitral and aortic valve heart diseases, to identify optimal timing for surgery and prognosticate outcomes after surgery

Myocardial Deformation Imaging Meta-Analysis in Two Cohorts of Patients from UAE and Heart Hospital Hamadmedical Corporation: A Potential Role in Assessment of Coronary Artery Disease Severity and Myocardial Viability

Introduction: The increasing prevalence of heart failure (HF) in coronary artery disease (CAD) urgently requires the establishment of new imaging techniques for early diagnosis and also to guide treatment of patients presented with acute coronary syndromes (ACS). Conventional echocardiography (CE) and electrocardiogram (ECG) are the gold standard methods in assessing myocardial ischemia (MI) and the function of the heart in patients with coronary artery disease (CAD). The lack of ST elevation by ECG and regional wall motion abnormalities by CE in non-ST segment elevation myocardial infarction (NSTEACS) in ACS patients reflect limited sensitivity of ECG and CE in identifying patients with acute coronary occlusion (ACO) and proper assessment of myocardial viability. Aim of this study: This study now evaluates the ability of strain parameters in grading the severity of CAD to detect myocardial viability in ACS through a comparative meta-analysis in two cohorts of patients living in the UAE and Qatar. The study investigates the diagnostic accuracy of left ventricular longitudinal systolic strain function (GLS) by 2D-speckle tracking echocardiography (2D-STE), Territorial Longitudinal Strain (TLS) analysis and post systolic strain (PSS) in ACS patients admitted at the emergency departments. All the patients had acute chest pain which is highly suggestive of NSTEACS along with coronary angiography (CA). Methods: The study recruited two groups, comprising of 347 patients, who were presented with acute coronary syndrome (NSTEACS) at the emergency department. The first group had 214 consecutive patients who had acute chest pain and high-risk profile and they were admitted to the emergency department at Eastern Emirates Hospitals, El-Fujairah-Dibba (EEEH), UAE. The second group consisted of 133 from emergency department at Heart Hospital- Hamad Medical Corporation (HHHMC), Qatar. In both groups, 85% of the patients were men with ages from 32 to 65 years (mean ± SD: 49.4 ± 9.5 years). Significant CAD was defined as having at least one epicardial vessel with ≥ 70% or left main>50% stenosis. All patients enrolled in this study underwent basic echocardiography, speckle tracking analysis, and coronary angiography. In 70 patients, PSS was calculated and myocardial perfusion imaging (MPI) was utilized as gold standards for the assessment of myocardial viability in patients with documented NSTEACS. The sensitivity, specificity, positive and negative predictive values of peak longitudinal systolic strain (2D-STE) and PSS were calculated. Left ventricular systolic strain was displayed as bull’s eye plot and territorial longitudinal strain (TLS) in the territory of the infarct-related artery. They were obtained within 24 hours from admission. Coronary angiography (CA) was performed within 24 hours from admission and used as a reference tests to assess the severity of CAD. Results: Echocardiogram obtained from the patients showed any no wall motion abnormalities at rest, although speckle tracking analysis was abnormal in 167 patients. In the first group of patients from the UAE, GLS showed a high sensitivity of 80% and a very high specificity of 93% for detection of significant CAD. In addition, PSS demonstrated a high sensitivity of 80% with an average specificity of 57%. The combination of GLS and PSS showed a further increase in sensitivity, specificity with positive and negative predictive values of 98%, 91%, 99% and 97%, respectively. Therefore, a very high correlation of GLS and PSS with coronary angiography was demonstrated: =0.90, p<0.0001 and R=0.88, p<0.0001, respectively. Furthermore, PSS showed a very high concordance with MPI scan (stress-rest-re injection studies) in detection of ischemic viable myocardium with very high sensitivity of 85%, r=0.79. In the Qatari (HHHMC) patients, a multi-vessel disease or left main disease (MV) was documented in 53.6%, and those with single vessel disease (SV) in 46.4%. LAD, circumflex and RCA lesions were found in 65, 50 and 39 patients, respectively. A control group of 129 cases was selected from outpatients referred to the echocardiography unit. The results showed that in comparison to CA, GLS sensitivity and specificity were 84% and 70%, respectively in all the patients. The sensitivity of GLS was 87% in MV and 80% in SV. Territorial strain sensitivity was 50%, 74% and 84.6% for the left anterior descending artery (LAD), circumflex and right coronary artery (RCA), respectively compared to specificity values of 64%, 65% and 61.7%, respectively. Conclusion: It is concluded that GLS by speckle tracking analysis is definitely an accurate method in early diagnosis of the severity of CAD in patients presenting with NSTE ACS. The combined use of GLS and PSS showed very high diagnostic accuracy for the identification of significant CAD in these patients. Strain imaging by STE may be applied to diagnose the severity of myocardial ischemia by showing reduction in peak systolic strain. Moreover, it is equally important to demonstrate post-systolic shortening which is a characteristic feature of ischemic viable myocardium after ACS requiring revascularization

Advanced Carotid Atherosclerosis and the Risk of Subsequent Major Cardiovascular Events: Carotid Ultrasound Study

Introduction: Very little is known about the role of atherosclerotic carotid plaque morphology, vulnerability, and Total Plaque Area (TPA) in the development of Major Cardiovascular Events (MCVE). Aim of this study: To assess the role of carotid atherosclerosis and the plaque morphology in the prediction of MCVE. Importance of the study: A better understanding of the role of detection of atherosclerosis and unstable plaque morphology can help to improve strategies for prevention of Acute Cardiovascular Events (ACVE) worldwide. Methods: This study analyzed the medical records of 452 patients with 2.5-years follow-up. The primary outcomes were the composite of first occurrence of stroke, cardiovascular death, and Acute Coronary Syndromes (ACS) hospitalization. Results: The results show that carotid atherosclerosis was present in 44% of patients (n=103) and this was associated with increasing conventional cardiovascular risk factors and extent of symptomatic vascular disease. During 2.5 years follow-up, 10% of patients experienced ≥ 2 MCVE. After adjustment for cardiovascular risk factors, the risk of ACS and stroke increased by 23% (95% Confidence Interval [CI]), and 45% (95% confidence interval), respectively in patients with carotid ultrasonic (US) evidence of advanced carotid atherosclerosis in comparison to control (P<0.001). The relative increase of cerebrovascular events was 22% in patients with carotid US evidence of vulnerable plaque morphology versus benign morphology. The high risk for all-cause and cardiovascular death of these patients remained significant after adjustment for various established cardiovascular risk factors in multivariable regression analysis (adjusted hazard ratio 2.4, P<0.001; compared to patients without US evidence of advanced carotid atherosclerosis features). Conclusion: It is concluded that carotid TPA and features of vulnerability were associated with an increased risk of MCVE

New Insight in the Assessment of Left Ventricular Function in Paradoxical Low Flow Aortic Stenosis Patients with Normal Left Ventricular Ejection Fraction: A Mini-Review

Paradoxical valvular aortic stenosis (VAS) is a challenging area of clinical cardiology for the practitioners. It involves a small aortic valve area, low flow rate and mean pressure gradient although there is normal left ventricular ejection fraction. The aim of this study was to assess left ventricular (LV) dysfunction in a symptomatic severe aortic valve stenosis which is of crucial importance in identifying patients at risk of heart failure, postoperative complications and increased mortality. There are new insights which are involved in assessment of LV myocardial function including global longitudinal strain (GLS) by two-dimensional speckle tracking echocardiography (2D STE), myocardial performance index (MPI) and maximum rate of LV pressure rise (+dP/dt) during isovolumetric contraction time of the LV. This information can provide both diagnostic and prognostic information in addition to standard echocardiographic and clinical parameters. However, a profound understanding of the complex interaction between loading conditions, chamber geometry and contractility is necessary for the correct interpretation of myocardial deformation in order to draw appropriate conclusions in patients with aortic valve disease. This mini review is related to new and novel insights into the assessment of left ventricular function (LVF) in paradoxical low flow aortic stenosis patients with normal left ventricular ejection fraction (LVEF)

New Insight in the Assessment of Left Ventricular Function in Paradoxical Low Flow Aortic Stenosis Patients with Normal Left Ventricular Ejection Fraction: A Mini Review

Paradoxical valvular aortic stenosis (VAS) is a challenging area of clinical cardiology for the practitioners. It involves a small aortic valve area, low flow rate and mean pressure gradient although there is normal left ventricular ejection fraction. The aim of this study was to assess left ventricular dysfunction in a symptomatic severe aortic valve stenosis which is of crucial importance in identifying patients at risk of heart failure, postoperative complications and increased mortality. There are new insights which are involved in assessment of LV myocardial function including global longitudinal strain (GLS), myocardial performance index (MPI) and maximum rate of LV pressure rise (+dP/dt) during isovolumetric contraction time of the ventricle. This information can provide both diagnostic and prognostic information in addition to standard echocardiographic and clinical parameters. However, a profound understanding of the complex interaction between loading conditions, chamber geometry and contractility is necessary for the correct interpretation of myocardial deformation in order to draw appropriate conclusions in patients with aortic valve disease. This mini review is related to new and novel insights into the assessment of left ventricular function (LVF) in paradoxical low flow aortic stenosis patients with normal left ventricular ejection fraction (LVEF)