HFpEF and Atrial Fibrillation: The Enigmatic Interplay of Dysmetabolism, Biomarkers, and Vascular Endothelial Dysfunction.

Background: Heart failure with preserved ejection fraction (HFpEF) has a complex pathophysiology that encompasses systemic proinflammatory state and dysregulated levels of cardiometabolic and oxidative stress biomarkers. The prevalence of both HFpEF and atrial fibrillation (AF) is continuously rising, especially in the elderly. The aim of our study was to explore if there were any differences in biomarker levels and vascular function in the elderly patients with HFpEF with and without AF and to assess interconnections between clinically relevant biomarkers and cardiac and vascular function. Methods: This was a cross-sectional study of patients ≥ 65 years with HFpEF who were divided into 2 groups based on the presence or absence of AF. We have sonographically assessed echocardiographic parameters of left ventricular systolic and diastolic function and the peripheral vascular function parameters, namely, pulse wave velocity (PWV) and flow-mediated dilation (FMD). NT-proBNP, irisin, leptin, adiponectin, insulin-like growth factor 1 (IGF-1), and malondialdehyde (MDA) blood levels were determined. Results: Fifty-two patients (mean age 80 ± 7 years, 67% females) were included. Patients with HFpEF and AF had significantly lower levels of irisin (median 4.75 vs. 13.5 ng/mL, p = 0.007), leptin (median 9.5 vs. 15.0 ng/L, p = 0.023), and MDA (median 293 vs. 450 ng/mL, p = 0.017) and significantly higher values of NT-proBNP (median 2365 vs. 529 ng/L, p < 0.001) but not vascular function parameters, as compared to HFpEF patients without AF. MDA was significantly correlated with diastolic function (r = 0.395, p = 0.007) and FMD (r = 0.394, p = 0.011), while adiponectin was inversely associated with FMD (r = -0.325, p = 0.038) and left ventricular ejection fraction (r = -0.319, p = 0.029). Conclusions: Our results have demonstrated that patients with HFpEF and AF have significantly lower leptin, irisin, and MDA levels compared to patients with HFpEF but without AF. These results offer new insights into the complexity of vascular function and cardiometabolic and oxidative stress biomarkers in the context of HFpEF, AF, and aging.

Exercise capacity improvement after cardiac rehabilitation following myocardial infarction and its association with long-term cardiovascular events.

AIMS: Cardiovascular rehabilitation (CR) improves aerobic capacity and quality of life in patients after myocardial infarction (MI). The aim was to examine the associations between exercise capacity improvement and different clinically relevant cardiovascular events. METHODS AND RESULTS: This was a registry-based study of post-MI patients, referred to CR. All patients were submitted to exercise testing before and after CR (36 sessions, 2-3 times/week, and combined exercise). Patients were divided into two groups, based on the difference in exercise capacity before and after the CR programme with the cut-off of two metabolic equivalents (METs) improvement. We assessed the correlation between the extent of exercise capacity improvement and the following cardiovascular events: major adverse cardiac events (MACE), cardiovascular-related hospitalizations, and unplanned coronary angiography. A total of 499 patients were included (mean age 56 ± 10 years, 20% women). Both groups significantly improved in terms of exercise capacity, natriuretic peptide levels, resting heart rate, and resting diastolic pressure; however, lipid status significantly improved only in patients with ≥2 METs difference in exercise capacity. A total of 13.4% patients suffered MACE (median follow-up 858 days); 21.8% were hospitalized for cardiovascular reasons (median follow-up 791 days); and 19.8% had at least one unplanned coronary angiography (median follow-up 791 days). Exercise capacity improvement of ≥2 METs was associated with lower rates of MACE, cardiovascular hospitalizations, and unplanned coronary angiography in all examined univariate and multivariate models. CONCLUSION: This study has shown that exercise improvement of ≥2 METs is associated with a significant decrease in MACE, cardiac hospitalizations, and unplanned coronary angiography.

Right Ventricular Perforation by a Defibrillator Lead Migrating to the Left Breast.

Cardiac perforation after an ICD implantation is a rare complication, with a reported incidence between 0.6-5.2%. Its manifestation might be acute, subacute, or delayed, with an acute perforation occurring within the first 24 hours after implantation, frequently accompanied by severe clinical signs, while subacute and delayed perforations have a more benign progression. Here, we report a case of a 69-year old patient with an acute right ventricular perforation by a defibrillator lead migrating all the way through the pericardium and thoracic wall into the left breast, with an unusually mild and benign clinical course, delaying prompt diagnosis and postponing subsequent surgical treatment. Heart perforation with a defibrillator electrode is a rare but dangerous complication, which may lead to pacing failure, cardiac tamponade, cardiogenic shock, and even death. Even with a benign clinical course, one must think of cardiac wall perforation at any time after device implantation, and a contrast enhanced computer tomography (CTA) must be performed if perforation is suspected. At re-implantation, the lead should be located at a different anatomical position within the RV, preferably at the interventricular septal site, and manipulation of the injury site within the RV avoided.

Effect of cardiac resynchronization therapy on beat-to-beat T-wave amplitude variability.

AIMS: T-wave amplitude variability (TAV) is a promising non-invasive predictor of arrhythmic events in patients with dilated cardiomyopathy. We aimed to evaluate the effect of cardiac resynchronization therapy (CRT) on native TAV, its relation with left ventricular (LV) reverse remodelling and the occurrence of ventricular tachyarrhythmias (VTs). METHODS AND RESULTS: In this prospective study, we included 40 heart failure patients with left bundle branch block in sinus rhythm (25 male; 16 with ischaemic aetiology; aged 62.7 ± 9.5 years; New York Heart Association class II-IV). Echocardiographic parameters and TAV were evaluated at baseline and 6 months after implantation of CRT device combined with an implantable cardioverter-defibrillator. T-wave amplitude variability was determined by a 20-min high-resolution electrocardiogram Holter recording during native conduction. After TAV assessment, patients were monitored for 15.7 ± 5.2 months for the occurrence of VTs. Decrease in median TAV [from 40.45 µV (24.75-56.00) to 28.15 µV (20.93-37.95), P = 0.004] was observed after 6 months of CRT. However, decrease of median TAV was only noticed in patients with LV reverse remodelling [46.9 µV (27.5-70.0) to 25.8 µV (20.2-32.4), P < 0.001] and in patients without VTs [40.5 µV (27.5-55.9) to 24.4 µV (17.1-31.5), P < 0.001]. Native median TAV > 35.4 µV after 6 months of CRT had an 83% sensitivity and 93% specificity for predicting the occurrence of VTs. CONCLUSIONS: Decrease of TAV after CRT is associated with LV reverse remodelling and indicates a reduction of the intrinsic arrhythmogenic substrate. Median TAV after CRT had a good predicting value for VT occurrence in long-term follow-up.

T-wave variability as a risk stratifier in patients with dilated cardiomyopathy.

BACKGROUND: T-wave alternans is an important identifier of patients at risk of sudden cardiac death (SCD), but the procedure usually requires stress testing. In this study, the variability of T-wave amplitude (TVAR) was evaluated at rest, as a risk stratifier for SCD. METHODS: This study included 57 patients in sinus rhythm and with a left ventricular ejection fraction < or =40%, of whom 34 (60%) received an implantable cardioverter-defibrillator (ICD) after surviving SCD, and 23 (40%) presented with ischemic or nonischemic cardiomyopathy and no history of SCD. A 20-minute high-resolution electrocardiographic recording for TVAR assessment was performed during supine rest. The vector magnitude was used as a primary lead for TVAR analysis. RESULTS: The mean, median, and maximum (max) values of TVAR were measured. The patients with ICD had a lower max TVAR than the patients without ICD (67 vs 95 muV; P = 0.045), though the mean and median TVAR values were similar. By multivariate logistic analysis, max TVAR remained a predictor of SCD, after adjustments for potentially confounding factors (P = 0.044). CONCLUSION: Max TVAR was a predictor of arrhythmic events in patients with dilated cardiomyopathy at rest.