Complete left bundle branch block and smaller left atrium are predictors of response to cardiac resynchronization therapy in advanced heart failure

Basic and advanced echocardiography in advanced heart failure: an overview

Advanced chronic heart failure (ACHF) is the last phase in the evolution of heart failure and is characterized by high hospitalization and mortality rates and is refractory to medical therapy, therefore requiring more aggressive therapies, such as mechanical circulatory support or heart transplantation. Over the last years, the incidence of ACHF was continuously growing, together with the increase in population survival rates. Therefore, the early recognition of the transition to ACHF is of crucial importance in HF patients, which also helps in prognostication of such patients, since advanced therapeutic options are limited to selected patients and they also have some important risk implications. Echocardiography is the gold standard tool for the evaluation of patients with HF; moreover, the recent technological advances provided new structural and functional indices of the four cardiac chambers that showed to be comparable to advanced imaging or invasive hemodynamic parameters. This allows us to operate an accurate study of ACHF with first- and second-level echocardiographic techniques, which are now being integrated in daily clinical practice. The present review presents an overview of the currently available tools for the echocardiographic examination of patients with ACHF, with its advantages and limitations, based on the latest supporting evidences.

The left atrium and the right ventricle: two supporting chambers to the failing left ventricle

Heart failure (HF) is mainly caused by left ventricular (LV) impairment of function, hence detailed assessment of its structure and function is a clinical priority. The frequent involvement of the left atrium (LA) and the right ventricle (RV) in the overall cardiac performance has recently gained significant interest with specific markers predicting exercise intolerance and prognosis being proposed. The LA and RV are not anatomically separated from the LV, while the LA controls the inlet the RV shares the interventricular septum with the LV. Likewise, the function of the two chambers is not entirely independent from that of the LV, with the LA enlarging to accommodate any rise in filling pressures, which could get transferred to the RV via the pulmonary circulation. In the absence of pulmonary disease, LA and RV function may become impaired in patients with moderate-severe LV disease and raised filling pressures. These changes can often occur irrespective of the severity of systolic dysfunction, thus highlighting the important need for critical assessment of the function of the two chambers. This review evaluates the pivotal role of the left atrium and right ventricle in the management of HF patients based on the available evidence.

Effect of cardiac resynchronization therapy on mitral valve geometry: a novel aspect as "reversed mitral remodeling"

Amelioration of the valvular geometry is a possible mechanism for mitral regurgitation (MR) improvement in patients receiving cardiac resynchronization therapy (CRT). We aimed to establish the precise definition, incidence, and predictors of reversed mitral remodeling (RMR), as well as the association with MR improvement and short-term CRT outcome. Ninety-five CRT recipients were retrospectively evaluated for the end-point of "MR response" defined as the absolute reduction in regurgitant volume (RegV) at 6 months. To identify RMR, changes in mitral deformation indices were tested for correlation with MR response and further analyzed for functional and echocardiographic CRT outcomes. Overall, MR response was observed in 50 patients (53%). Among the echocardiographic indices, the change in tenting area (TA) had the highest correlation with the change in RegV (r = 0.653, p < 0.001). The mean TA significantly decreased in MR responders (4.15 ± 1.05 to 3.67 ± 1.01 cm² at 6 months, p < 0.001) and increased in non-responders (3.68 ± 1.04 to 3.98 ± 0.97 cm², p = 0.014). The absolute TA reduction was used to identify patients with RMR (47%) which was found to be associated with higher rates of functional improvement (p = 0.03) and volumetric CRT response (p = 0.036) compared to those without RMR. Non-ischemic etiology and the presence of LBBB independently predicted RMR at multivariate analysis. In conclusion, reduction in TA is a reliable index of RMR, which relates to MR response, and functional and echocardiographic improvement with CRT. LBBB and non-ischemic etiology are independent predictors of RMR.

Indication of Ventricular Assist Device Therapy in Patients with INTERMACS Profile 4-7

Optimal timing of ventricular assist device (VAD) therapy has been discussed mainly among patients with heart failure dependent on inotrope infusion, but little is known about the indication of VAD therapy among less sick ambulatory patients. Considering recent improvement of VAD therapy outcome, now is the best time to discuss the expansion of VAD indication into less sick population. In this review, we will investigate optimal candidates for VAD therapy especially among ambulatory populations on the basis of recent evidence.

Determinants of Left Ventricular Systolic Function Improvement Following Coronary Artery Revascularization in Heart Failure Patients With Reduced Ejection Fraction (HFrEF)

Revascularization therapy such as percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) should be considered for heart failure with reduced ejection fraction (HFrEF). However, revascularization therapy does not always improve left ventricular ejection fraction (LVEF). The purpose of this study was to investigate the determinants of LVEF improvement following revascularization in HFrEF patients. From 2,229 consecutive decompensated heart failure patients, a total of 47 HFrEF patients who underwent revascularization were included in the analysis. Improvement of LVEF was defined as [(LVEF during chronic phase) - (LVEF during acute phase)] ≥ 10%. Univariate and multivariate logistic regression analyses were applied to investigate the determinants of LVEF improvement. The prevalence of revascularization by PCIs including chronic total occlusion (CTO) was significantly greater in the improved EF group (45.0%) as compared to the non-improved EF group (11.1%) (P = 0.02). Multivariate logistic regression analysis revealed that revascularization by PCIs including CTO was the significant determinant of the LVEF improvement after adjusting for confounding factors (OR 5.43, 95% CI 1.06-27.74, P = 0.04). Optimal medical therapy (angiotensin-converting enzyme (ACE) inhibitor and/or angiotensin II receptor blocker (ARB) and beta-blockers) was less frequently prescribed in patients with CABG (50.0% for ACE inhibitor and/or ARB and 41.7% for beta-blocker) than in patients without CABG (94.3% for both) (P < 0.01 and P < 0.001, respectively). In conclusion, revascularization by PCIs including CTO was the significant determinant of LVEF improvement in HFrEF patients. Our results underscore the importance of optimal medical therapy even if patients receive complete revascularization such as CABG.