Assessment of Cardiac Damage in Aortic Stenosis

Cardiac dysfunction rather than aortic valve stenosis severity drives exercise intolerance and adverse haemodynamics

AIMS

To study the impact of heart failure with preserved ejection fraction (HFpEF) vs. aortic stenosis (AS) lesion severity on left ventricular (LV) hypertrophy, diastolic dysfunction, left atrial (LA) dysfunction, haemodynamics, and exercise capacity.

METHODS AND RESULTS

Patients (n = 206) with at least moderate AS (aortic valve area ≤0.85 cm/m2) and discordant symptoms underwent cardiopulmonary exercise testing with simultaneous echocardiography. The population was stratified according to the probability of underlying HFpEF by the heavy, hypertension, atrial fibrillation, pulmonary hypertension, elder, filling pressure (H2FPEF) score [0-5 (AS/HFpEF-) vs. 6-9 points (AS/HFpEF+)] and AS severity (Moderate vs. Severe). Mean age was 73 ± 10 years with 40% women. Twenty-eight patients had Severe AS/HFpEF+ (14%), 111 Severe AS/HFpEF- (54%), 13 Moderate AS/HFpEF+ (6%), and 54 Moderate AS/HFpEF- (26%). AS/HFpEF+ vs. AS/HFpEF- patients, irrespective of AS severity, had a lower LV global longitudinal strain, impaired diastolic function, reduced LV compliance, and more pronounced LA dysfunction. The pulmonary arterial pressure-cardiac output slope was significantly higher in AS/HFpEF+ vs. AS/HFpEF- (5.4 ± 3.1 vs. 3.9 ± 2.2 mmHg/L/min, respectively; P = 0.003), mainly driven by impaired cardiac output and chronotropic reserve, with signs of right ventricular pulmonary arterial uncoupling. AS/HFpEF+ vs. AS/HFpEF- was associated with a lower peak aerobic capacity (11.5 ± 3.7 vs. 15.9 ± 5.9 mL/min/kg, respectively; P < 0.0001) but did not differ between Moderate and Severe AS (14.7 ± 5.5 vs. 15.2 ± 5.9 mL/min/kg, respectively; P = 0.6).

CONCLUSION

A high H2FPEF score is associated with a reduced exercise capacity and adverse haemodynamics in patients with moderate to severe AS. Both exercise performance and haemodynamics correspond better with intrinsic cardiac dysfunction than AS severity.

Fragmented QRS complex may predict long-term mortality after isolated surgical aortic valve replacement in patients with severe aortic stenosis

OBJECTIVES

Fragmented QRS (fQRS), related to myocardial fibrosis, is an important prognostic marker of cardiovascular events and mortality. Aortic stenosis (AS), the most frequent valvular heart disease in developed countries, causes myocardial fibrosis due to ventricular pressure overload. The current study aimed to investigate whether fQRS is associated with long-term mortality after isolated surgical aortic valve replacement (SAVR) in patients with severe AS.

METHODS

A total of 289 patients who underwent SAVR for severe AS between May 2009 and January 2020 with interpretable electrocardiogram were included. Patients were divided into 2 groups according to the presence of fQRS. Kaplan-Meier survival analyses were used to detect cumulative survival rates. Univariable and multivariable Cox proportional hazards models were used to determine the predictors of all-cause mortality.

RESULTS

fQRS occurred in 126 (43.5%) patients. A total of 59 (20.4%) patients died over a follow-up period of 54 ± 32 months. All-cause mortality was higher in the fQRS group (23 [14.1%] vs 36 [28.6], log-rank test P = 0.002) in the long term. The presence of fQRS [hazard ratio (HR): 1.802, confidence interval (CI): 1.035-3.135, P = 0.037], electrocardiographic left ventricular strain (HR: 1.836, CI: 1.036-3.254, P = 0.038) and history of stroke or transient ischaemic attack (HR: 3.130, CI: 1.528-6.412, P = 0.002) were independent predictors of all-cause mortality in the multivariable Cox regression model.

CONCLUSIONS

fQRS is associated with a 1.8-fold increase in long-term mortality in patients undergoing isolated SAVR for severe AS. Detecting fQRS in electrocardiograms may provide prognostic information about the long-term outcomes.

Efficacy of Whole-Blood Del Nido Cardioplegia Compared with Diluted Del Nido Cardioplegia in Coronary Artery Bypass Grafting: A Retrospective Monocentric Analysis of Pakistan

Background and Objectives: Cardioplegia is one of the most significant components used to protect the myocardium during cardiac surgery. There is a paucity of evidence regarding the utilization of whole-blood Del Nido cardioplegia (WB-DNC) on clinical outcomes in coronary artery bypass grafting (CABG). The purpose of this retrospective cross-sectional study is to compare the effectiveness of diluted (blood to crystalloid; 1:4) Del Nido cardioplegia (DNC) with WB-DNC in patients who underwent elective CABG in a tertiary care hospital in Lahore-Pakistan. Materials and Methods: This was a retrospective descriptive study conducted at the Department of Cardiovascular Surgery, King Edward Medical University, Lahore. The medical database of all consecutive patients admitted from January 2018 to March 2020 and who fulfilled the inclusion criteria were reviewed. Results: Out of 471 patients admitted during the study period, 450 underwent various elective cardiac surgeries. Out of 450, 321 patients (71.33%) were operated on for CABG. Only 234/321 (72.89%) CABG patients fulfilled our inclusion criteria; 120 (51.28%) patients received WB-DNC, while 114 (48.71%) patients were administered with DNC. The former group presented with better clinical outcomes compared with the latter in terms of lesser requirements of inotropic support, low degree of hemodilution, shorter in-hospital stay, improved renal function, and cost-effectiveness. Peak values of serum Troponin-T (Trop-T), creatine kinase-myocardial band (CK-MB) release, and activated clotting time (ACT) were also lower in the WB-DNC group compared with the DNC group. Conclusions: The WB-DNC conferred better myocardial protection, improved early clinical outcomes, and also proved to be economical for patients undergoing elective CABG compared with classical crystalloid cardioplegia solution.

Left ventricular asymmetric remodeling and subclinical left ventricular dysfunction in patients with calcific aortic valve stenosis - Results from a subanalysis of the PROGRESSA study

BACKGROUND

LV asymmetric remodeling (LVAR) is a feature commonly found in AS patients and it is presumed to be mainly related to the severity of valve stenosis. The aim of this study was to determine the associated factors and impact on left ventricular (LV) systolic function of LVAR in patients with mild and moderate aortic valve stenosis (AS).

METHODS

Clinical, Doppler-echocardiographic and computed-tomographic data of 155 AS patients with preserved LV ejection fraction (≥50%) prospectively recruited in the PROGRESSA study (NCT01679431) were analyzed. LVAR was defined as a septal wall thickness ≥ 13 mm and a ratio of septal/posterior wall thickness > 1.5. LV global longitudinal strain (LV-GLS) was available in 129 patients. Plasma levels of N-terminal natriuretic B-type peptides (Nt-proBNP) were also measured.

RESULTS

Mean age was 63 ± 15 years (70% men). LVAR was present in 21% (n = 33) of patients. A series of nested multivariate analysis revealed that age was the only factor associated with LVAR (all p ≤ 0.03). Additionally, these patients had higher baseline Nt-proBNP ratio (median [25-75 percentiles]: 1.04 [0.66-2.41] vs. 0.65 [0.33-1.19], p = 0.02), and significantly reduced LV-GLS (17.9[16.6-19.5] vs. 19.3[17.4-20.7] |%|, p = 0.04). A 1:1 matched analysis showed a significant association of LVAR with reduced LV-GLS (17.9[16.6-19.5] vs. 19.8[18.1-20.7] |%|, p = 0.02) and elevated Nt-proBNP (134[86-348] vs. 83[50-179]pg/ml, p = 0.03). Multivariable analysis also revealed that LVAR remains significantly associated with reduced LV-GLS (p = 0.03) and elevated Nt-proBNP (p = 0.001). LVAR was significantly associated with increased risk of major adverse cardiac events and death (Hazard ratio [95% confidence interval]: 2.32[1.28-4.22], p = 0.006).

CONCLUSIONS

LVAR was found in ~20% of patients with mild or moderate AS and was not related to the degree of AS severity or concomitant comorbidities, but rather to older age. LVAR was significantly associated with reduced LV longitudinal systolic function, increased Nt-proBNP levels, and higher risk of major adverse events and death. These findings provide support for closer clinical and echocardiographic surveillance of patients harboring this adverse LV remodeling feature.