Tsuda Takeshi, Walczak Amy, O'Neil Karen
Nemours Cardiac Center, Nemours Children's Health Delaware, 1600 Rockland Rd., Wilmington, DE 19803, USA.
Department of Pediatrics, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA 19107, USA.
J Cardiovasc Dev Dis. 2025 Jul 23;12(8):280. doi: 10.3390/jcdd12080280.
The onset of cardiomyopathy in Duchenne muscular dystrophy (DMD) is insidious and poorly defined. We proposed integrated wall stress (iWS) as a marker of total left ventricular (LV) workload and tested whether the increased iWS represents early DMD cardiomyopathy.
Peak systolic wall stress (PS-WS) was calculated in M-mode echocardiography with simultaneous blood pressure measurement. iWS was defined as a product of PS-WS and heart rate (HR) divided by 60 (=PS-WS/RR interval). We measured iWS in normal controls (CTRL), DMD with normal LV shortening fraction (%LVSF ≥ 30%) (DMD-A), and DMD with decreased %LVSF (<30%) (DMD-B).
40 CTRL and 79 DMD patients were studied. Despite comparable %LVSF, both HR and iWS were significantly higher in DMD-A (n = 50) than in CTRL ( < 0.0001). iWS was significantly higher in DMD-B (n = 29) than in DMD-A ( < 0.0001) despite comparable HR. PS-WS was significantly higher in DMD-A than in CTRL and higher in DMD-B than in DMD-A, suggesting high HR is not a sole determinant of increased iWS in DMD-A compared with CTRL. In a longitudinal study in 35 DMD patients over 4.0 ± 2.0 years, iWS showed significant increase ( = 0.0062) alongside a significant decline in %LVSF ( < 0.0001).
iWS significantly increased in DMD before %LVSF declined. The progressive increase of iWS in DMD is initially associated with increased HR and then with increased PS-WS. iWS may serve as a useful echocardiographic marker in identifying preclinical DMD cardiomyopathy.
杜氏肌营养不良症（DMD）中心肌病的发病隐匿且定义不明确。我们提出综合壁应力（iWS）作为左心室（LV）总工作量的标志物，并测试iWS升高是否代表早期DMD心肌病。
在M型超声心动图中同时测量血压，计算收缩期峰值壁应力（PS-WS）。iWS定义为PS-WS与心率（HR）的乘积除以60（=PS-WS/RR间期）。我们在正常对照组（CTRL）、左心室缩短分数正常（%LVSF≥30%）的DMD患者（DMD-A）和%LVSF降低（<30%）的DMD患者（DMD-B）中测量了iWS。
研究了40名CTRL患者和79名DMD患者。尽管%LVSF相当，但DMD-A组（n = 50）的HR和iWS均显著高于CTRL组（<0.0001）。尽管HR相当，但DMD-B组（n = 29）的iWS显著高于DMD-A组（<0.0001）。DMD-A组的PS-WS显著高于CTRL组，DMD-B组的PS-WS高于DMD-A组，这表明与CTRL组相比，高HR不是DMD-A组iWS升高的唯一决定因素。在对35名DMD患者进行平均4.0±2.0年的纵向研究中，iWS显著增加（=0.0062），同时%LVSF显著下降（<0.0001）。
在%LVSF下降之前，DMD患者的iWS显著增加。DMD患者iWS的逐渐增加最初与HR增加有关，然后与PS-WS增加有关。iWS可能是识别临床前DMD心肌病的有用超声心动图标志物。
