Outcomes in hypertrophic cardiomyopathy patients with and without atrial fibrillation: a survival meta-analysis.
BACKGROUND
Atrial fibrillation (AF) is a frequent occurrence in patients with hypertrophic cardiomyopathy (HCM). It is associated with worsening symptoms, cardiovascular events, and mortality. We conducted a meta-analysis of studies reporting on mortality in patient with HCM and AF.


METHODS
We searched PubMed, Medline, Embase, Ovid and Cochrane for studies which reported cardiovascular events and mortality in patients with HCM and AF. Outcome was a composite of cardiac mortality and/or all-cause mortality. Mantel Haenszel odds ratio (OR) or hazard ratio (HR) were calculated using random-effects meta-analysis for the prespecified outcome. Heterogeneity was assessed using I2statistics.


RESULTS
Six studies met the inclusion criteria. There were 6,858 patients; 1,314 (19%) had history of AF. During a mean follow up that ranged between 4 and 8 years, 405 (30.8%) patients with AF died as compared to 1,011 (18.2%) patients without AF (OR =2.49, 95% CI: 1.85-3.35, P<0.00001, I2=57%). Results persisted with inclusion of studies only reporting specifically on cardiac mortality (OR =2.80, 95% CI: 1.79-4.39, P<0.00001, I2=56%). Also, the mortality difference persisted after exclusion of deaths secondary to stroke in both groups (2 studies, 1,398 patients, OR =2.57, 95% CI: 1.57-4.20, P=0.0002, I2=31%). In three studies (5,857 patients); the presence of AF was associated with a pooled HR of 1.66 (95% CI: 1.29-2.13, P<0.0001, I2=41%).


CONCLUSIONS
Patients with HCM who develop AF have higher risk of mortality and cardiac deaths as compared to HCM patients without AF.
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Ahmad
A
Masri
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Mohamed
M
Kanj
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Maran
M
Thamilarasan
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Oussama
O
Wazni
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Nicholas G
NG
Smedira
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Harry M
HM
Lever
Hypertrophic Cardiomyopathy Center, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Milind Y
MY
Desai
Hypertrophic cardiomyopathy; atrial fibrillation; meta-analysis; outcomes