Autosomal Dominant Polycystic Kidney Disease (ADPKD) is associated with early onset hypertension, left ventricular (LV) hypertrophy and diastolic dysfunction. Early diastolic untwisting rate has emerged as a sensitive parameter of LV diastolic function. Two-dimensional speckle tracking echocardiography is a reproducible, non-invasive technique to quantify LV rotational mechanics throughout the whole cardiac cycle.
In this pre-specified, matched-cohort study we explored in 35 ADPKD patients with normal renal function or mild to moderate renal insufficiency from the ALADIN study and in 35 -matched controls renal disease no adpkd patients and evaluated the correlates of LV untwisting rate in this population. Speckle tracking echocardiography analysis was performed on 3 consecutive cardiac cycles. Rotation (degrees) and rotation rate (degrees/sec) profiles in basal and apical short-axis planes were measured. Instantaneous LV twist and twist rate were calculated by subtracting basal rotation from apical rotation and basal rotation rate from apical rotation rate, respectively, at corresponding time points in the cardiac cycle. LV untwisting rate was calculated as the early diastolic negative peak on LV twist rate curve.
The demographic, clinical and main laboratory data from ADPKD patients are listed in the table 1. A considerable percentage of ADPKD patients were hypertensive (68%). As compared to control, patients exhibited similar heart rate and blood pressure (BP), higher LV mass index, left atrium volume, and early diastolic mitral wave ( E) to early diastolic mitral annulus wave (Ea) ratio as well as lower global systolic longitudinal strain, LV twist and untwisting rate (Table 2). At multivariate analysis, LV mass index, diastolic BP and LV twist resulted significantly associated to untwisting rate (Table 3).
In conclusion, this study demonstrates an impairment of LV twisting dynamics in patients with early stage of ADPKD and provides insight into the LV diastolic dysfunction. The new parameters of cardiac function, derived from two-dimensional speckle-tracking echocardiography, could be useful for an early diagnosis of cardiac involvement in patients with ADPKD. Whether they can be used to assess the progression of disease and the response to the therapy is an issue to be pursued.