Valor pronóstico a largo plazo de la prueba de esfuerzo cardiopulmonar en pacientes con miocardiopatía hipertrófica

Hypertrophic cardiomyopathy (HCM) is a heterogeneous myocardial disorder characterized by left ventricular hypertrophy. The role of cardiopulmonary exercise testing (CPET) in predicting major adverse cardiac events (MACE) remains incompletely understood, particularly over long-term follow-up and independently of baseline symptoms.

We longitudinally studied 154 HCM patients (age 43 ± 16 years; 27% female), who underwent symptom-limited CPET. At baseline, 98 patients were in New York Heart Association (NYHA) Class I, 48 in Class II, and 8 in Class III. Septal reduction therapies (SRT), progression to end-stage HCM (ES-HCM), sudden cardiac death (SCD), heart failure-related death (HF), and heart transplantation (HT) represented a composite MACE endpoint.

Over a mean follow-up of 12 ± 9 years, 38 patients experienced MACE (SRT = 9; ES-HCM = 11; SCD = 10; HF/HT = 8). In multivariable analysis, independent predictors of MACE were percentage predicted peak VO2 (PVO2%) < 60 [hazard ratio (HR) 4.16, 95% confidence interval (CI) 1.89-9.14; P < .001], and NYHA Class >I (HR 2.27, 95% CI 1.06-4.89; P = .036). By using SRT as a competing risk, the only predictor of MACE became PVO2% < 60 (HR 3.966, 95% CI 1.626-9.670; P = .002). Among asymptomatic patients (i.e. NYHA Class I), only PVO2% < 60 remained a significant predictor of MACE (HR 5.611, 95% CI 1.635-19.253; P = .006), with risk divergence evident after nearly 15 years of follow-up. The result was also confirmed in the competing risk analysis.

In this long follow-up study, CPET is a powerful prognostic tool in HCM. A reduced peak VO2 identifies those at higher risk, highlighting the potential for CPET to improve risk stratification, even among patients classified as NYHA Class I.