P046: ANESTHETIC IMPLICATIONS OF LITHOTRIPSY ASSISTED TRANS-FEMORAL AORTIC VALVE REPLACEMENT
Adriana Martini, MD; Sofia Lifgren, MD; Asif Mohammed, MD; Jackson Memorial Hospital/ UM
Introduction: Trans-femoral Transcatheter Aortic Valve Replacement (TAVR) is performed with aid of large bore delivery systems. Severely calcified vessels have been a contraindication to utilizing trans-femoral access. In this case report we describe the use of intravascular lithotripsy (IVL), to enable trans-femoral delivery of transcether valve. The patient was a 79 years old female with severe shortness of breath (SOB) oxygen dependent due to critical aortic stenosis (AS), poorly controlled hypertension (HTN), type II diabetes mellitus, renal insufficiency, cirrhosis, and history of deep vein thrombosis (DVT) who was referred for TAVR due to comorbidities, age and frailty. Transthoracic Echocardiography (TTE) demonstrated severe aortic sclerosis and stenosis with aortic valve area via continuity equation of 0.58cm^2, aortic max pressure gradient of 63.4 mmHg and aortic mean pressure gradient of 36.0 mmHg. The 1st attempt of TAVR was unsuccessful as there was significant calcifications and narrowing of the abdominal aorta above the iliac bifurcation. After multiple attempts, interventional cardiologists were unable to pass the Edwards 14 French (Fr) 36 mm Sheath. As patient would not tolerate open surgical replacement of the aortic valve, in order to ensure percutaneous delivery of 14 Fr Edwards Sheath the circumferential calcified plaques were treated by use of 5.0mm x60mm peripheral IVL Balloon. After undergoing 4 lithotripsy runs where there was good balloon expansion under low pressure, the 14 Fr Edwards Sheath was inserted and advanced without incident. Patient had successful deployment of a Sapien 3 22mm valve with TTE demonstrating trace aortic insufficiency, no effusion and no perivalvular leak. As TAVR procedures are being performed with increasing frequency on patients with multiple comorbidities, the cardiac anesthesiologist must be adept at managing an array of hemodynamic and physiologic responses. This case represents an example where careful planning and preparation by the anesthesiologist of an innovative approach to TAVR yielded successful results.
Discussion: IVL works by disrupting vessel calcification allowing for the safe passage of large bore delivery sheaths thus expanding the patients eligible for trans-femoral access for TAVR procedures. This intervention spares patients from the more surgical intensive approaches, such as trans-apical, requiring thoracotomy and trans-aortic. In this case IVL use was reminiscent of aortic cross clamping where the hemodynamic response consists of increases in arterial pressure, systemic valve resistance (SVR), and decrease cardiac output (CO). Upon release of the balloon, blood flow is restored however it may trigger an ischemia reperfusion response leading to pathophysiological reactions such as inflammation and metabolic derangements that can lead to multi-organ dysfunction. Furthermore, with the IVL use there was a higher risk for embolic disease, aortic rupture and aortic dissection. For the anesthesiologist it is paramount to understand these processes and be prepared to treat them in order to allow for safe surgical outcome.