Genotype doesn't predict A-fib in hypertrophic cardiomyopathy

(HealthDay)—For patients with hypertrophic cardiomyopathy (HC), genotype does not predict onset or severity of atrial fibrillation (AF), according to a study published in the April 1 issue of The American Journal of Cardiology.

Carolina Bongini, M.D., from the Careggi University Hospital in Florence, Italy, and colleagues examined the prevalence and clinical profile of AF in 237 patients with HC who were followed for 14 ± 10 years. Patients were divided according to genotype: MYBPC3, MYH7, and "other genotypes" (58, 28, and 14 percent, respectively).

The researchers found that in all three groups, left atrial size was similar. AF occurred in 31 percent of patients with HC, with no significant difference according to genotype group (P = 0.15); there were also no between-group differences in paroxysmal/persistent AF (P = 0.53), paroxysmal/persistent evolved to permanent AF (P = 0.36), or permanent AF (P = 0.82). The group with other genotypes had younger age at AF onset (37 ± 10 years) compared with the other groups (53 ± 14 and 51 ± 17 years, respectively; P = 0.05). Atrial diameter (P ≤ 0.05) and age at diagnosis (P = 0.09), but not genetic subtype (P = 0.35), were independent predictors of AF in multivariate analysis.

"In patients with HC, genetic testing cannot be used in clinical decision making with regard to management strategies for AF," the authors write.