Transcatheter solutions for transcatheter aortic valve replacement dysfunction: is redo transcatheter aortic valve replacement a durable option?

Degenerated Transcatheter Aortic Valve Replacement: Investigation and Management Options

With the expansion of transcatheter aortic valve replacement (TAVR) to younger and lower-surgical-risk patients, many younger and less comorbid patients will be treated with TAVR and are expected to have a life expectancy that will exceed the durability of their transcatheter heart valve. Consequently, the number of patients requiring reintervention will undoubtedly increase in the near future. Redo-TAVR and TAVR explantation followed by surgical aortic valve replacement are the different therapeutic options in the event of bioprosthetic valve failure and the need for reintervention. Patients often anticipate being able to benefit from a redo-TAVR in the event of bioprosthetic valve failure after TAVR, despite the lack of long-term data and the risk of unfavourable anatomy. Our understanding of the feasibility of redo-TAVR is constantly improving thanks to bench test studies and growing worldwide experience. However, much remains unknown. In clinical practice, one of the heart team's objectives is to anticipate the need to reaccess the coronary arteries and implant a second or even a third valve when life expectancy may exceed the durability of the transcatheter heart valve. In this review, we address key definitions in the diagnosis of structural valve deterioration and bioprosthetic valve failure, as well as patient selection and procedural planning for redo-TAVR to reduce periprocedural risk, optimise hemodynamic performance, and maintain coronary access. We describe the bench testing and literature in the redo-TAVR and TAVR explantation fields.

Transcatheter aortic valve replacement in the management of aortic insufficiency secondary to left ventricular assist device implantation: a case report

Background

Left ventricular assist device (LVAD) is considered either a destination therapy for patients with end-stage heart failure or heart transplantation bridging. LVAD implantation often causes aortic insufficiency (AI), which requires aortic valve repair. However, severe acute AI does not respond well to medication, and re-operation means higher risk to the patients; the most effective therapeutic strategies for LVAD-induced AI still need further exploration. In this report, we present the first described case of new-onset, severe LVAD-induced AI in China with a patient who underwent transcatheter aortic valve replacement (TAVR) and achieved significant improvement in functional capacity and symptoms with lower operation risk.

Case Description

A 55-year-old male patient was diagnosed with dilated cardiomyopathy for 14 years. The effect of the medication gradually deteriorated, LVAD (HeartCon®) was implanted one year earlier. The patient complained of intermittent chest tightness for one week, which had been aggravated for two days before hospitalization. Echocardiographic findings revealed new-onset, severe LVAD-induced AI. TAVR was performed with a self-expandable stent-valve (TAV30, Vitaflow Liberty). Within minutes, the patient recovered with rapid disappearance of chest tightness and stable vital signs. Before discharge, the position of the artificial valve was fixed without incomplete closure nor thrombus attachment, yielding a left ventricular ejection fraction (LVEF) of 35%. The patient was hospitalized for 38 days, and followed up with outpatient treatment, the condition was stable until 19 June 2023.

Conclusions

TAVR could be an effective, safe, and less invasive means of restoring ejection fraction for patients with a LVAD who develop severe AI.

Right ventricular outflow tract obstruction associated with neointimal tissue accumulation and distortion of the Harmony TPV25 stent frame: Potential mechanisms and treatment

BACKGROUND

The Harmony TPV25 transcatheter pulmonary valve (Medtronic Inc.) is constructed with a self-expanding stent frame comprising six zigged nitinol wires sewn together and covered with knitted polyester fabric, with flared inflow and outflow ends and a porcine pericardial valve sutured to the central portion of the device. It was approved for treatment of pulmonary regurgitation after prior right ventricular outflow tract repair in 2021. Early outcomes of this procedure have been excellent, but little is known about valve durability or ultimate mechanisms of dysfunction.

METHODS

We collected data on patients who underwent reintervention for TPV25 dysfunction and described findings related to distortion of the stent frame and tissue accumulation.

RESULTS

We describe six patients who underwent valve-in-valve implant for TPV25 obstruction (peak catheterization gradient peak 28-73 mmHg) 10-28 months after implant. In all cases, there was tissue accumulation within the inflow and valve-housing segments of the device and deformation of the self-expanding valve frame characterized by variable circumferential narrowing at the junction between the valve housing and the inflow and outflow portions of the device, with additional geometric changes in all segments. All six patients underwent valve-in-valve implant that results in a final peak gradient ≤10 mmHg and no regurgitation.

DISCUSSION

The occurrence of short-term Harmony TPV25 dysfunction in multiple patients with a similar appearance of frame distortion and tissue accumulation within the inflow and valve housing portions of the device suggests that this may be an important failure mechanism for this valve. Potential causes of the observed findings are discussed. It is possible to treat this mechanism of TPV25 dysfunction with valve-in-valve implant using balloon expandable transcatheter valves.