Department of Cardiology, University Medical Center Utrecht, Utrecht, TheNetherlands.
Netherlands Heart Institute, Utrecht, TheNetherlands.
Eur Heart J Cardiovasc Imaging. 2022 Oct 20;23(11):1492-1501. doi: 10.1093/ehjci/jeab178.
Phospholamban (PLN) p.Arg14del mutation carriers are at risk of developing malignant ventricular arrhythmias (VAs) and/or heart failure. Currently, left ventricular ejection fraction (LVEF) plays an important role in risk assessment for VA in these individuals. We aimed to study the incremental prognostic value of left ventricular mechanical dispersion (LVMD) by echocardiographic deformation imaging for prediction of sustained VA in PLN p.Arg14del mutation carriers.
We included 243 PLN p.Arg14del mutation carriers, which were classified into three groups according to the '45/45' rule: (i) normal left ventricular (LV) function, defined as preserved LVEF ≥45% with normal LVMD ≤45 ms (n = 139), (ii) mechanical LV dysfunction, defined as preserved LVEF ≥45% with abnormal LVMD >45 ms (n = 63), and (iii) overt LV dysfunction, defined as reduced LVEF <45% (n = 41). During a median follow-up of 3.3 (interquartile range 1.8-6.0) years, sustained VA occurred in 35 individuals. The negative predictive value of having normal LV function at baseline was 99% [95% confidence interval (CI): 92-100%] for developing sustained VA. The positive predictive value of mechanical LV dysfunction was 20% (95% CI: 15-27%). Mechanical LV dysfunction was an independent predictor of sustained VA in multivariable analysis [hazard ratio adjusted for VA history: 20.48 (95% CI: 2.57-162.84)].
LVMD has incremental prognostic value on top of LVEF in PLN p.Arg14del mutation carriers, particularly in those with preserved LVEF. The '45/45' rule is a practical approach to echocardiographic risk stratification in this challenging group of patients. This approach may also have added value in other diseases where LVEF deterioration is a relative late marker of myocardial dysfunction.
磷酸化肌球蛋白结合蛋白 C（PLN）p.Arg14del 突变携带者有发生恶性室性心律失常（VA）和/或心力衰竭的风险。目前，左心室射血分数（LVEF）在这些个体的 VA 风险评估中起着重要作用。我们旨在通过超声心动图应变成像研究左心室机械弥散（LVMD）对 PLN p.Arg14del 突变携带者持续性 VA 预测的额外预后价值。
我们纳入了 243 名 PLN p.Arg14del 突变携带者，根据“45/45”规则将其分为三组：（i）正常左心室（LV）功能，定义为保留的 LVEF≥45%且 LVMD≤45ms（n=139）；（ii）机械性 LV 功能障碍，定义为保留的 LVEF≥45%且 LVMD>45ms（n=63）；（iii）明显的 LV 功能障碍，定义为 LVEF<45%（n=41）。在中位随访 3.3 年（四分位间距 1.8-6.0 年）期间，35 名患者发生持续性 VA。基线时具有正常 LV 功能的阴性预测值为 99%[95%置信区间（CI）：92-100%]，用于发生持续性 VA。机械性 LV 功能障碍的阳性预测值为 20%（95%CI：15-27%）。多变量分析显示机械性 LV 功能障碍是持续性 VA 的独立预测因子[VA 病史调整后的危险比：20.48（95%CI：2.57-162.84）]。
LVMD 在 PLN p.Arg14del 突变携带者中的预后价值高于 LVEF，尤其是在保留 LVEF 的患者中。“45/45”规则是对这组具有挑战性的患者进行超声心动图风险分层的一种实用方法。这种方法在 LVEF 恶化是心肌功能障碍的相对晚期标志物的其他疾病中也可能具有额外的价值。
