Renal function as a predictor of outcomes in patients with hypertrophic cardiomyopathy: A cohort study of a hospitalized population

Mildly Reduced Renal Function Is Associated With Increased Heart Failure Admissions in Patients With Hypertrophic Cardiomyopathy

BACKGROUND

The association between renal dysfunction and cardiovascular outcomes has yet to be determined in patients with hypertrophic cardiomyopathy (HCM). We aimed to investigate whether mildly reduced renal function is associated with the prognosis in patients with HCM.

METHODS

Patients with HCM were enrolled at two tertiary HCM centers. Patients who were on dialysis, or had a previous history of heart failure (HF) or stroke were excluded. Patients were categorized into 3 groups by estimated glomerular filtration rate (eGFR): stage I (eGFR ≥ 90 mL/min/1.73 m², n = 538), stage II (eGFR 60-89 mL/min/1.73 m², n = 953), and stage III-V (eGFR < 60 mL/min/1.73 m², n = 265). Major adverse cardiovascular events (MACEs) were defined as a composite of cardiovascular death, hospitalization for HF (HHF), or stroke during median 4.0-year follow-up. Multivariable Cox regression model was used to adjust for covariates.

RESULTS

Among 1,756 HCM patients (mean 61.0 ± 13.4 years; 68.1% men), patients with stage III-V renal function had a significantly higher risk of MACEs (adjusted hazard ratio [aHR], 2.71; 95% confidence interval [CI], 1.39-5.27; P = 0.003), which was largely driven by increased incidence of cardiovascular death and HHF compared to those with stage I renal function. Even in patients with stage II renal function, the risk of MACE (vs. stage I: aHR, 2.21' 95% CI, 1.23-3.96; P = 0.008) and HHF (vs. stage I: aHR, 2.62; 95% CI, 1.23-5.58; P = 0.012) was significantly increased.

CONCLUSION

This real-world observation showed that even mildly reduced renal function (i.e., eGFR 60-89 mL/min/1.73 m²) in patients with HCM was associated with an increased risk of MACEs, especially for HHF.

Protective Effect of Catheter Ablation of Atrial Fibrillation on the Renal Function in Patients With Hypertrophic Cardiomyopathy

Atrial fibrillation (AF) is a common arrhythmia in patients with hypertrophic cardiomyopathy (HCM) and is associated with renal function deterioration. The protective effects of catheter ablation (CA) of AF on renal function in patients with HCM remain unsolved. From 2009 to 2020, a total of 169 consecutive patients with HCM and AF (age 70 ± 12, 87 males) were retrospectively evaluated. The estimated glomerular filtration rate (eGFR) was evaluated at the study enrollment or 1 month before the CA and reevaluated 3 and 12 months later. In the 169 patients, 63 underwent CA of AF (ablation group), and the remaining 106 did not (control group). After propensity score matching, 45 pairs were matched. The baseline eGFR was similar between the 2 groups (p = 0.83). During a mean follow-up period of 34 ± 27 months, sinus rhythm was maintained in 36 patients (80%) after 1.7 ± 0.8 ablation procedures. The eGFR significantly decreased from baseline to 3 months (p <0.01) and from baseline to 1 year (p <0.01) in the control group, whereas the eGFR in the ablation group was maintained both from baseline to 3 months (p = 0.94) and from baseline to 1 year (p = 1.00) after the CA. The change in the eGFR between baseline and 12 months was significantly smaller in the ablation group than in the control group (p <0.01). After logistic regression analysis, CA of AF was the independent predictor of an improvement of eGFR (odds ratio 2.81, 95% confidence interval 1.08 to 7.36, p = 0.04). In conclusion, CA of AF had a protective effect on renal function in patients with HCM.

Age, creatinine clearance, and ejection fraction (mACEF) score predicts long-term cardiac mortality in patients with hypertrophic obstructive cardiomyopathy treated non-invasively

OBJECTIVE

Presently, an effective model to predict long-term cardiac mortality in patients with hypertrophic obstructive cardiomyopathy (HOCM) is lacking. Therefore, the objective of this study was to evaluate the predictive value of the modified Age, Creatinine clearance, and Ejection Fraction (mACEF) score for long-term cardiac mortality in patients with HOCM.

METHODS

Two hundred and ninety two patients with HOCM treated non-invasively were enrolled in this study, all of whom had intact medical information.

RESULTS

Over a median follow-up period of 41.9 months, 28 cardiac deaths occurred. In univariate Cox regression analysis, the mACEF score was associated with long-term cardiac death [hazard ratio (HR)=1.795, 95% confidence interval (CI) 1.518-2.124, p<0.001]. Multiple Cox regression analysis identified the mACEF score as an independent risk factor for long-term cardiac death (adjusted HR=1.372, 95% CI 1.076-1.749, p=0.011). Analysis of the receiver operating characteristic (ROC) for long-term cardiac death showed that the mACEF score had a considerable predictive value (area under ROC 0.844, sensitivity 89.29%, specificity 75.00%) with an optimum cut-off value of 0.96. The study population was divided into high-risk (mACEF score ≥0.96, n=91) and low-risk (mACEF score <0.96, n=201) groups according to the optimum cut-off value. Kaplan-Meier survival analysis was performed and showed a dramatic higher rate of long-term cardiac mortality in the high-risk group than in the low-risk group (27.4% vs. 1.7%, p<0.001 by log-rank test).

CONCLUSION

The mACEF score has a considerable predictive value for long-term cardiac mortality in patients with HOCM treated non-invasively. A mACEF score ≥0.96 could be considered as a sign of poor prognosis in patients with HOCM.