Combined Transcatheter Aortic Valve Replacement and Emergent Alcohol Septal Ablation

Abstract

A 91-year-old woman presented with worsening exertional dyspnea. Her previous medical history included hypertension, percutaneous coronary intervention with drugeluting stent placement to the mid left anterior descending coronary artery, moderate bilateral carotid atherosclerosis, and moderate chronic obstructive pulmonary disease.Transthoracic echocardiography revealed a normal left ventricular ejection fraction with asymmetric upper septal hypertrophy (posterior wall, 1.3 cm; interventricular septum, 2.0 cm; Figure 1A) but without left ventricular outflow tract (LVOT) obstruction ( Figure 1B) at rest or with a Valsalva maneuver. There was severe aortic valve calcification and stenosis ( Figure 1A and 1C).The patient was referred for transcatheter aortic valve replacement (AVR) via the transfemoral approach. Upon crossing the stenotic aortic valve, the peak-to-peak left ventricle-aorta (LVAo) pressure gradient was recorded at 60 mm Hg (Figure 2A). After deployment of a 23-mm Edwards SAPIEN prosthesis, the patient became hypotensive and the peak-to-peak LV-Ao gradient was recorded at 120 mm Hg ( Figure 2B). Transesophageal echocardiography demonstrated a properly functioning aortic prosthesis and revealed a dynamic obstruction in the LVOT attributable to systolic anterior motion of the mitral valve ( Figure 3A), associated with severe mitral regurgitation ( Figure 3B).After review of the preprocedural coronary angiogram ( Figure 4A), the decision was made to proceed emergently to alcohol septal ablation to relieve the dynamic LVOT obstruction. Isopropyl alcohol (1.5 mL) was infused in the septal perforator, and subsequent angiography revealed occlusion of the vessel ( Figure 4B). Transesophageal echocardiography revealed marked reduction in systolic anterior motion and in the degree of LVOT obstruction and mitral regurgitation, as well ( Figure 5). Hemodynamic tracings demonstrated almostcomplete resolution of the LV-Ao gradient ( Figure 6).The patient was successfully extubated at the conclusion of the case and was discharged from the hospital 5 days later. At 1-month follow-up, transthoracic echocardiography revealed continued reduction in the LV-Ao gradient at rest (15 mm Hg) and minimal increase with provocation by a Valsalva maneuver (18 mm Hg). DiscussionIn patients with aortic stenosis, hypertrophy of the left ventricular myocardium often occurs as a result of the increased myocardial load imposed by the valvular obstruction. In most cases, the hypertrophy is concentric, although some patients present with an asymmetric upper septal hypertrophy with or without dynamic LVOT obstruction. 1-3Our patient demonstrated severe asymmetric upper septal hypertrophy, but had no evidence of LVOT obstruction on dynamic preoperative testing. Upon implantation of the transcatheter prosthesis, however, she developed significant LVOT obstruction. This is likely the result of a number of physiological and anatomic changes. The relationship between afterload and LVOT obstruction has been elucidated by numerous investigators...

Alcohol septal ablation in patients with concomitant hypertrophic cardiomyopathy and aortic valvular stenosis

“…For example, in patients who are thought to have a primarily fixed obstruction related to severe AS, proceeding with TAVR and its associated afterload reduction may lead to a significant increase in the dynamic LVOT obstruction, as seen in Cases 5 and 6. Post‐TAVR septal ablation was effective at relieving the dynamic LVOT obstruction in these patients and this result is consistent with prior reports . Conversely, patients with untreated severe valvular AS who have relatively mild dynamic LVOT obstruction and undergo alcohol septal ablation first may be at increased risk of heart failure and arrhythmias due to potential worsening of diastolic function with ablation.…”

“…Post-TAVR septal ablation was effective at relieving the dynamic LVOT obstruction in these patients and this result is consistent with prior reports. [8][9][10][11] Conversely, patients with untreated severe val- based on these principles is described in Figure 3.…”

“…Alcohol septal ablation has the potential to improve symptoms in patients who are thought to have a significant contribution from dynamic LVOT obstruction. It has been previously described in patients with coexistent AS both prior to and after TAVR . Despite this, the feasibility, safety, and efficacy of alcohol septal ablation in this setting remains unclear as existing data is limited solely to case reports in the literature.…”

“…It has been previously described in patients with coexistent AS both prior to and after TAVR. [6][7][8][9][10][11] Despite this, the feasibility, safety, and efficacy of alcohol septal ablation in this setting remains unclear as existing data is limited solely to case reports in the literature. In this series, we describe the hemodynamic and early clinical outcomes of percutaneous alcohol septal ablation in six patients with serial left ventricular outflow obstructions due to HCM and AS.…”

Association of Hypertrophic Obstructive Cardiomyopathy With Outcomes Following Transcatheter Aortic Valve Replacement

“…Current data on the association between HCM and postprocedural outcomes after TAVR are limited to small case reports and case series, which have described acute hemodynamic compromise after valve deployment. [1][2][3] These cases highlight the difficulty in determining the contributions of each of the 2 obstructive lesions, and that provocable gradients might best be treated prior to TAVR to avoid the so-called suicide ventricle due to rapid removal of the afterload of aortic stenosis. [1][2][3] The increased mortality observed in our study is likely attributable to unanticipated postprocedural hemodynamic compromise caused by unmasking of left ventricular outflow tract obstruction due to HCM, as previously reported.…”