Deceleration Capacity of Heart Rate Predicts Arrhythmic and Total Mortality in Heart Failure Patients.

BACKGROUND: Deceleration capacity (DC) of heart rate proved an independent mortality predictor in postmyocardial infarction patients. The original method (DCorig) may produce negative values (9% in our analyzed sample). We aimed to improve the method and to investigate if DC also predicts the arrhythmic mortality. METHODS: Time series from 221 heart failure patients was analyzed with DCorig and a new variant, the DCsgn, in which decelerations are characterized based on windows of four consecutive beats and not on anchors. After 41.2 months, 69 patients experienced sudden cardiac death (SCD) surrogate end points, while 61 died. RESULTS: (SCD+ vs SCD-group) DCorig: 3.7 ± 1.6 ms versus 4.6 ± 2.6 ms (P = 0.020) and DCsgn: 4.9 ± 1.7 ms versus 6.1 ± 2.2 ms (P < 0.001). After Cox regression (gender, age, left ventricular ejection fraction, filtered QRS, NSVT≥1/24h, VPBs≥240/24h, mean 24-h QTc, and each DC index added on the model separately), DCsgn (continuous) was an independent SCD predictor (hazard ratio [H.R.]: 0.742, 95% confidence intervals (C.I.): 0.631-0.871, P < 0.001). DCsgn ≤ 5.373 (dichotomous) presented 1.815 H.R. for SCD (95% C.I.: 1.080-3.049, P = 0.024), areas under curves (AUC)/receiver operator characteristic (ROC): 0.62 (DCorig) and 0.66 (DCsgn), P = 0.190 (chi-square). Results for deceased versus alive group: DCorig: 3.2 ± 2.0 ms versus 4.8 ± 2.4 ms (P < 0.001) and DCsgn: 4.6 ± 1.4 ms versus 6.2 ± 2.2 ms (P < 0.001). In Cox regression, DCsgn (continuous) presented H.R.: 0.686 (95% C.I. 0.546-0.862, P = 0.001) and DCsgn ≤ 5.373 (dichotomous) presented an H.R.: 2.443 for total mortality (TM) (95% C.I. 1.269-4.703, P = 0.008). AUC/ROC: 0.71 (DCorig) and 0.73 (DCsgn), P = 0.402. CONCLUSIONS: DC predicts both SCD and TM. DCsgn avoids the negative values, improving the method in a nonstatistical important level.

The natural history of multifocal atrial rhythms in elderly outpatients: insights from the "Ikaria study".

BACKGROUND: Multifocal atrial tachycardias confer an adverse prognosis in hospitalized patients. We assessed the prognostic impact of multifocal atrial rhythms (MARs-either chaotic atrial rhythm or multifocal atrial tachycardia/bradycardia) in very elderly outpatients. METHODS: One hundred ten subjects aged 60-74 years, 112 aged 75-89 years, and 61 over 90 years old, were enrolled and prospectively evaluated. Several demographic and clinical characteristic were recorded in all individuals. RESULTS: A high prevalence of MARs was detected in the study population (namely, 6%), which in subjects >90 years was even higher (15%). Individuals with MARs were older, more often female and less active. In multivariate analysis, independent predictors of MARs were age (OR = 1.07, 95% CI: 1.02-1.13, P = 0.01) and female sex (OR = 4.77, 95% CI: 1.23-18.48, P = 0.02). The mortality rate during the follow-up period was 8.4% without differences between age groups (P = 0.209). In particular, mortality rate was 6% in individuals with MARs and 9% in those without (P = 0.72). Mortality was associated with age (OR 1.07, 95% CI: 1.02-1.12, P = 0.005) and history of cardiovascular disease at baseline (OR 4.57, 95% CI: 1.87-11.2 P = 0.001). CONCLUSIONS: Contrary to hospitalized individuals with multifocal atrial tachycardias, MARs were not associated with increased mortality in elderly outpatients in this study.

Mitral valve in hypertrophic cardiomyopathy: a three-dimensional transesophageal study.

BACKGROUND: It is reported that the mitral valve (MV) in hypertrophic cardiomyopathy (HCM) has structural abnormalities. PURPOSE: To assess the MV in HCM patients using Three-Dimensional Transesophageal Echocardiography (3DTEE). METHODS: Transthoracic and 3DTEE studies focused on the mitral valve were performed prospectively in 21 HCM patients with obstruction (Group I), 37 HCM patients without obstruction (Group II) and 28 controls (Group III). RESULTS: The aortomitral angle was less obtuse in groups I and II compared with group III (104.6 ± 6.7° vs 107.6 ± 8.5° vs 112.9 ± 3.2°, p < 0.001) and the annulus height was larger (11.6 ± 1.3 mm vs 11.6 ± 2 mm vs 9.3 ± 1.1 mm, p < 0.001). Patients in group I compared with groups II and III had increased ratio of anterior leaflet length to left ventricular outflow tract (LVOT) diameter (1.9 ± 0.1 vs 1.7 ± 0.3 vs 1.3 ± 0.1, p < 0.05) and anterior displacement of the coaptation line as showed by the reduced ratio of anterior to posterior leaflet length in the projection plane (1.7 ± 0.4 mm vs 2.2 ± 0.7 mm vs 2.4 ± 0.7 mm, p < 0.05). In groups I and II there was a positive correlation between the MV annulus height and the presence of non-sustained ventricular tachycardia (rs = 0.25, p < 0.05). CONCLUSION: The MV in HCM patients with or without obstruction shares some common anatomic features. Additionally, the MV in patients with obstruction has unique characteristics that appear to contribute to LVOT obstruction.

Effect of gender on the prognostic value of dobutamine stress myocardial contrast echocardiography.

BACKGROUND: Dobutamine stress contrast echo (DSCE) has a well-established prognostic value in the context of coronary artery disease (CAD). However, data regarding its prognostic capability separately in men and women are scarce. The aim of the current study was to assess gender-related differences in the prognostic performance of DSCE. METHODS: DSCE was performed in 2645 consecutive patients, who were classified into two groups depending on gender. Follow-up lasted 57.1±10.1 months. End points included all-cause mortality, cardiac death, late revascularization, and hospitalizations. Survival analysis was performed comparing men and women. RESULTS: Of the 2645 patients (59.3±8.7 years), 69.1% were men. DSCE was positive in 23.4% of male patients, while in females, the respective percentage was 14.3%. There was statistically significant difference between the two groups with regard to end point occurrence (11.6% vs. 6.1%, p<0.05). Multivariate analysis revealed that the DSCE response was the strongest predictor of adverse outcomes (Exp(B)=51.9, p<0.05) in both groups. The predictive model including DSCE results along with clinical data performed well without significant differences between males and females (C-index 0.93 vs. 0.87 respectively, p=NS). CONCLUSION: DSCE has a strong prognostic value for patients with known or suspected CAD, regardless of patient gender. This makes DSCE an attractive screening option for women in whom CAD assessment can be challenging.