Correlation of left ventricular hypertrophy parameters and MRI derived left ventricular mass in hypertrophic cardiomyopathy
█ Original article
Nagy Viktória1, Pálinkás Attila2, Tóth Levente3, Takács Hedvig1, Gavallér Henriette1, Simor Tamás4, Forster Tamás1, Sepp Róbert1
1Szegedi Tudományegyetem, II. sz. Belgyógyászati Klinika és Kardiológiai Központ, Szeged
2Erzsébet Kórház, Belgyógyászati Osztály, Hódmezővásárhely
3Pécsi Tudományegyetem, Radiológiai Klinika, Pécs
4Pécsi Tudományegyetem, Szívgyógyászati Klinika, Pécs
Background: The magnitude and distribution of left ventricular hypertrophy (LVH) shows a remarkable variety in patients with hypertrophic cardiomyopathy (HCM). To characterise LVH in HCM, several LVH parameters has been traditionally used in clinical practice. In our study we aimed to look for correlation between traditional LVH parameters and MRI derived left ventricular mass (LVM) in patients with HCM.
Patients and methods: The patient study cohort included 44 HCM patients (27 males, average age: 43±16 yrs). Cardiac MRI examination was performed according to standard methods and left ventricular mass (LVMMRI) was determined. Correlation was looked for between LVMMRI and the following left ventricular hypertrophy parameters: maximal left ventricular wall thickness (LVmax), Maron-Spirito score, Weigle score, number of hypertrophized LV segments, and left ventricular mass calculated from echocardiographic parameters, using the Deveraux equation (LVMecho). LVMMRI has been correlated with the average left ventricular wall thickness (LVaverage), defined as the average thickness of the standard 16 left ventricular segments.
Results: All the LVH parameters showed a significant, although not strong correlation with LVMMRI. LVmax, the most frequently used parameter to characterised LVH in HCM, showed the weakest correlation with LVMMRI (r=0.385; p=0.01), and the Maron-Spirito score showed also a weak correlation (r=0.518; p=0.0004). The Wiegle score and the number of hypertrophized LV segments showed a correlation coefficient ³0.6 (r=0.600, p=0.0001; 0.643; p <0.0001, respectively). The best correlation was observed between LVMMRI and LVaverage (r=0.678; p <0.0001). Although a weak, but significant correlation was seen between LVMMRI and LVMecho (r=0.445; p=0.0028), according to the Bland-Altman analysis, LVMecho markedly overestimate real LVM (average difference: –194.9 g, ±1.96 SD: 46.0 to –435.8 g).
Conclusion: Parameters, traditionally used to characterise left ventricular hypertrophy in HCM, show weak correlation with cardiac MRI derived left ventricular mass in patients with HCM. Therefore, it seems imperative to investigate the prognostic influence and clinico-morphological correlates of LV mass as an independent parameter in patients with hypertrophic cardiomyopathy.