Determinants of peak oxygen uptake in patients with hypertrophic cardiomyopathy: a single-center study

作者：Magri Damiano; Agostoni Piergiuseppe^*; Cauti Filippo Maria; Musumeci Beatrice; Assenza Gabriele Egidy; De Cecco Carlo Nicola; Muscogiuri Giuseppe; Maruotti Antonello; Ricotta Agnese; Pagannone Erika; Marino Laura; Santini Daria; Proietti Giulia; Serdoz Andrea; Paneni Francesco; Volpe Massimo; Autore Camillo

来源：Internal and Emergency Medicine, 2014, 9(3): 293-302.

DOI：10.1007/s11739-012-0866-x

• Hypertrophyc cardiomyopathy
• Cardiopulmonary exercise test
• Chronotropic incompetence

Most patients with hypertrophic cardiomyopathy (HCM) usually complain of a reduced exercise capacity, and several factors have been advocated as possible causes of this clinical feature. The present single-center study was designed to investigate exercise capacity and its main clinical determinants in HCM patients. One hundred ninety seven patients of 223 evaluated underwent a complete clinical assessment, including Doppler echocardiography, cardiopulmonary exercise test (CPET) and, in most cases, cardiac magnetic resonance. The HCM population (male 75 %; age 47 +/- 16 years; NYHA class I or II 95 %; left ventricular ejection fraction 61 +/- 3 %; resting left ventricular outflow tract gradient >= 30 mmHg 22 %; late gadolinium enhancement presence 58 %) showed slightly reduced mean peak oxygen uptake values (pVO(2) 75 +/- 15 %, 23.2 +/- 6.7 ml/kg/min) with a significant reduction of the achieved percentage of peak heart rate reserve (%pHRR 65 +/- 20 %). Adopting a pVO(2) <80 % cut-off value, 59 % of HCM patients showed a reduced exercise capacity. Age, male gender, left atrial size, chronotropic and systolic blood pressure response, ventilatory efficiency, late gadolinium enhancement presence and beta-blocker therapy were independently associated with pVO(2) (R-2-adjusted index 0.738). A %pHRR cut-off value of 74 % appeared to most accurately predict an impaired exercise capacity (area under curve 0.90). A great prevalence of reduced exercise capacity is present in NYHA class I-II HCM patients. Notwithstanding its multifactorial genesis, few parameters might be adopted in identifying this feature. In this context, %pHRR value might represent a reliable and easy-to-obtain tool for the clinical evaluation of HCM patients.

• 出版日期2014-4