Sharma Avneesh, Kaplan Emily, Betz Yaqub, Ayers Michael
Division of Cardiovascular Medicine, University of Virginia Health System, Charlottesville, VA 22902, USA.
Eur Heart J Case Rep. 2025 Jun 28;9(7):ytaf312. doi: 10.1093/ehjcr/ytaf312. eCollection 2025 Jul.
Hypertrophic cardiomyopathy (HCM) is a relatively common genetic disorder often associated with left ventricular outflow tract (LVOT) obstruction. However, the presence of certain structural abnormalities such as supravalvular aortic stenosis (SVAS) can contribute to elevated LVOT gradients and thereby mimic obstructive HCM. This case highlights the importance of multimodality imaging in accurately determining the aetiology of LVOT obstruction, which is critical to guiding appropriate management.
A 27-year-old male with progressive dyspnoea, fatigue, and recent syncope was initially diagnosed with obstructive HCM based on transthoracic echocardiography (TTE) findings of severe left ventricular hypertrophy and a mid-cavitary gradient exceeding 100 mmHg with Valsalva. Genetic testing for HCM was negative. Cardiac magnetic resonance (CMR) imaging confirmed concentric hypertrophy with asymmetric septal involvement and also suggested atypical flow acceleration. Prior to planned septal myectomy, transoesophageal echocardiography (TEE) revealed a supravalvular aortic membrane with a resting gradient of 55 mmHg. Given this finding, the surgical plan was modified, and the patient underwent excision of the fibrotic ring and aortic reconstruction. Postoperatively, the supravalvular gradient resolved and the patient reported symptomatic relief.
When evaluating LVOT obstruction, the limitations of TTE in assessing supravalvular structures can lead to diagnostic error. Patients with suspected HCM who are being evaluated for surgical management should also undergo TEE and CMR to assess the supravalvular aorta for potential SVAS contributing to an elevated LVOT gradient. Incorporating multimodality imaging in these patients enhances diagnostic accuracy, accurately directs surgical planning, and reduces the risk of proceeding with unnecessary intervention.
肥厚型心肌病（HCM）是一种相对常见的遗传性疾病，常与左心室流出道（LVOT）梗阻相关。然而，某些结构异常的存在，如主动脉瓣上狭窄（SVAS），可导致LVOT梯度升高，从而模拟梗阻性HCM。本病例强调了多模态成像在准确确定LVOT梗阻病因中的重要性，这对于指导恰当的治疗至关重要。
一名27岁男性，有进行性呼吸困难、疲劳和近期晕厥症状，最初根据经胸超声心动图（TTE）显示的严重左心室肥厚以及瓦尔萨尔瓦动作时中腔梯度超过100 mmHg的结果被诊断为梗阻性HCM。HCM基因检测为阴性。心脏磁共振（CMR）成像证实为同心性肥厚，伴有不对称的室间隔受累，还提示有非典型血流加速。在计划进行室间隔心肌切除术前，经食管超声心动图（TEE）显示主动脉瓣上有一膜状物，静息梯度为55 mmHg。鉴于这一发现，手术计划被修改，患者接受了纤维化环切除和主动脉重建术。术后，主动脉瓣上梯度消失，患者报告症状缓解。
在评估LVOT梗阻时，TTE在评估主动脉瓣上结构方面的局限性可能导致诊断错误。对疑似HCM且正在接受手术治疗评估的患者，还应进行TEE和CMR检查，以评估主动脉瓣上区域是否存在可能导致LVOT梯度升高的SVAS。对这些患者采用多模态成像可提高诊断准确性，准确指导手术规划，并降低进行不必要干预的风险。
