Long-term follow-up of subvalvular aortic stenosis in children: a single-centre experience

Objective: The aim of this study is to evaluate clinical and surgical outcomes of children with subaortic stenosis, to determine the risk factors for surgery and reoperation and to compare isolated subaortic stenosis and those concomitant with CHDs. Methods: The study involved 80 children with subaortic stenosis. The patients were first classified as isolated and CHD group, and the isolated group was further classified as membranous/fibromuscular group. The initial, pre-operative, post-operative and the most recent echocardiographic data, demographic properties and follow-up results of the groups were analysed and compared. The correlation of echocardiographic parameters with surgery and reoperation was evaluated. Results: There was a significant male predominance in all groups. The frequency of the membranous type was higher than the fibromuscular type in the whole and the CHD group. The median time to the first operation was 4.6 years. Thirty-five (43.7%) patients underwent surgery, 5 of 35 (14%) patients required reoperation. The rate of surgery was similar between groups, but reoperation was significantly higher in the isolated group. The gradient was the most important factor for surgery and reoperation in both groups. In the isolated group besides gradient, mitral-aortic separation was the only echocardiographic parameter correlated with surgery and reoperation. Conclusion: Reoperation is higher in isolated subaortic stenosis but similar in membranous and fibromuscular types. Early surgery may be beneficial in preventing aortic insufficiency but does not affect the rate of reoperation. Higher initial gradients are associated with adverse outcomes, recurrence and reoperation.

Abstract 17189: Radiation-induced Accelerated Multi-valve Disease In A Patient With Subaortic Membrane

A 69-year-old woman with history of right breast cancer status post lumpectomy and radiation (4.2 cGy) 18 months prior, presented with progressive NYHA class III dyspnea. TTE obtained prior to her cancer diagnosis was notable for normal LV size and wall thickness, a subaortic membrane with systolic mean Doppler gradient of 21 mmHg and a mildly thickened mitral valve without significant stenosis or regurgitation. On presentation, TTE was notable for severely increased concentric LV wall thickness (LV mass index 140 g/m 2 ), preserved ejection fraction, increased RV wall thickness, subaortic stenosis with systolic mean Doppler gradient 35 mmHg, moderate-severe aortic regurgitation, thickened mitral valve with posterior leaflet tethering and anterior leaflet override causing severe mitral regurgitation and moderate mitral stenosis (valve area 1.7 cm 2 by pressure half-time). She underwent a surgical intervention with septal myectomy, subaortic membrane resection, aortic root reconstruction, aortic and mitral valve replacement with bioprostheses. She did well post-operatively and had complete resolution of symptoms following cardiac rehabilitation. Radiation-induced valvular heart disease is linked to the total dose of radiation, use of sequential chemotherapy and time since irradiation, with a typical latency of 10-20 years. However, there is paucity of data regarding the influence of these variables in patients with pre-existing valve disease. This case illustrates dramatic acceleration of underlying aortic and mitral valve pathology in a patient with a subaortic membrane, 18 months after radiation. We also noted development of significant concentric LV hypertrophy that was disproportionate to the degree of obstruction across the sub-aortic membrane. Potential candidates for radiation therapy must be carefully screened for pre-existing valve disease, which should warrant increased vigilance and early screening for progressive valve disease.

Identification and Clinical Significance of Heart Murmurs in Puppies Involved in Puppy Trade

The detection of a congenital heart defect at purchase is an important step in early detection from a clinical and legal standpoint. Indeed, some cardiac abnormalities may be corrected with surgery, and very often, treatment needs to be performed early before congestive heart failure or irreversible heart damage can occur. From a legal viewpoint, if the defect is revealed in a newly purchased puppy, the buyer may be required to return it and receive compensation. Puppies affected with congenital heart defects are likely to die prematurely, causing emotional suffering to the owner. Furthermore, by considering breed predisposition, early recognition allows breeders to avoid breeding from particular dogs with genetic defects and prevent the continuation of genetic defects in breeding lines. Given gaps in the literature about the recognition of murmurs in the puppy trade, the present article describes how to identify a heart murmur in a puppy during a pre-purchase examination and its significance from a clinical and legal viewpoint. In the canine population, the prevalence of cardiac defects ranges between 0.13 and 1.6%. Pulmonic stenosis is the most common defect found in puppies, followed by patent ductus arteriosus, subaortic stenosis, and ventricular septal defect. On the basis of the above considerations, the veterinarian should recognize and identify the murmur following a protocol for routine examination of puppies involved in trade.

Long-Term Functional Results of Patients Operated for Isolated Discrete Subaortic Stenosis

Background: This study aimed to examine the long-term functional results of patients with isolated discrete subaortic stenosis who underwent subaortic membrane resection and myectomy, using transthoracic M-mode echocardiography and 2D speckle-tracking echocardiography. Methods: Twenty patients operated for isolated discrete subaortic stenosis and 31 controls were included in the study. Patients underwent subaortic membrane resection and myectomy. During the long-term follow up, patients were evaluated with transthoracic M-mode echocardiography and 2D speckle-tracking echocardiography for functional assessment. Results: The mean age at operation and mean duration of follow up was 8.1±5.6 years and 7.2±3.3 years, respectively. Interventricular septal thickness at diastole (0.9±0.1 vs. 0.8±0.1 cm, P = 0.001), ejection time (285.7±26.2 vs. 261.2±24.3 msec, P = 0.001), and aortic strain (15.6±3.7 vs. 10.5±4.0, P < 0.001) were significantly higher in patients. On the other hand, ejection fraction (64.9±6.1 vs. 75.1±5.4 %, P < 0.001), fractional shortening (35.0±5.1 vs. 43.7±5.1, P < 0.001), and corrected velocity circumferential fiber shortening (0.12±0.02 vs. 0.17±0.03, P < 0.001) were significantly lower, when compared with the controls. Longitudinal strain value significantly differed among the groups, with patients having significantly lower strain (18.8±1.8 vs. 20.1±2.1, P = 0.021). Conclusion: In patients operated for isolated discrete subaortic stenosis, aortic gradient seems to continue in the long-term, with the persistence of low longitudinal strain.

Redo aortic valve reconstruction as saving surgery in a patient with severe rheumatoid cardiac disease.

The combination of aortic valve regurgitation, rheumatoid aortitis, and subaortic stenosis is not frequent in patients with rheumatoid arthritis. Moreover, the surgical treatment of these entities may be challenging with non-adequate results. We report a case of a patient with severe aortic valve regurgitation, inaccessible aortic root secondary to rheumatoid aortitis, and severe subaortic stenosis initially treated by aortic valve replacement. We reoperated the patient due to acute prosthetic valve failure performing an aortic valve reconstruction using bovine pericardium and Ozaki’s technique with good outcomes.

Surgical repair of subaortic stenosis resection: 10 years of single-center experience in 65 patients

Background Subaortic stenosis (SAS) was a rare congenital heart disease of left ventricular outflow tract (LVOT), ranging from “isolated” lesions to “tunnel” or “diffuse” lesions. We conducted a retrospective study to describe the characteristics of patients with different lesions and analyze the risk factors for reoperation. Methods In this study, we examined a single-center retrospective cohort of SAS patients undergoing resection from 2010 to 2019. Patients were classified as simple lesion group (n = 37) or complex lesion group (n = 28). Demographics, perioperative findings, and clinical data were analyzed. Results The surgical effect of the two groups was significantly lower than that before the operation (p <0.05). The median age at operation was 6(3-11.8) years. There was no operative mortality. In complex lesion group, extracorporeal circulation time (CPB time), aortic cross clamp time (ACC time), mechanical ventilation time and ICU stay time were longer. The median follow-up period was 2.8 years (range 1-3.8), with two late death. Six patients (9.2%) required reoperation due to restenosis or severe aortic insufficiency. The freedom from reoperation rates at 5 years was 66.7% for simple lesion but only 52.3% for complex lesion (p = 0.036). Conclusions Although the lesions include many forms, subaortic stenosis resection was still satisfactory. However, the reoperation after initial surgical treatment was not infrequent, especially in patients with complex lesion.