Variables associated with contrast-enhanced cardiovascular magnetic resonance in hypertrophic cardiomyopathy: clinical implications.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) shows increased myocardial collagen and disarray. Late gadolinium enhancement in cardiovascular magnetic resonance (CMR) is observed in regions of increased myocardial collagen. The extent of late gadolinium enhancement has been associated with higher prevalence of risk factors of sudden death. The aim of the present study was to describe the clinical characteristics and the presence of risk factors for sudden death in a series of patients from 2 referral centers for HCM in relation to late gadolinium enhancement in CMR.

METHODS AND RESULTS: A total of 120 patients (47 +/- 16 years) were included. All patients fulfilled conventional criteria for HCM. A complete history and clinical examination were performed. Risk factors for sudden death were evaluated. A blinded CMR was performed with late gadolinium enhancement in the left ventricular short-axis orientation. NT pro B-type natriuretic protein (BNP) and C-reactive protein were determined in serum samples. A total of 83 patients (69%) showed late gadolinium enhancement. These patients had higher maximal left ventricular wall thickness (22 +/- 5 versus 17 +/- 3 mm, P < .001), showed more frequently obstruction (42% versus 16%, P = .006), nonsustained ventricular tachycardia (38% versus 8%, P = .001), worse exercise capacity (8 +/- 4 versus 10 +/- 4 METs, P = .003) and increased levels of NT BNP (656 [300-1948] versus 290 [122-948] pg/mL, P = .020). On multivariate analysis, maximal left ventricular wall thickness (P < .001) and nonsustained ventricular tachycardia (P = .011) remained associated with gadolinium-enhanced imaging. Number of risk factors for sudden death was associated with late gadolinium enhancement (OR 2.18, 95%CI 1.45-3.20, P < .001).

CONCLUSIONS: Late gadolinium enhancement in CMR is a common finding in HCM. Increased maximal left ventricular wall thickness and nonsustained ventricular tachycardia are associated with late gadolinium enhancement. Associations with risk factors for sudden death and functional status are observed.