Cronología y evolución de los trastornos de conducción asociados con el implante percutáneo de válvula aórtica: impacto de la valvuloplastia aórtica con balón

Dependência de Pacing a Longo-Prazo e Preditores de Implante de Pacemaker após Implante Percutâneo de Prótese Valvular Aórtica – 1 Ano de Seguimento

Fundamento

Os distúrbios de condução (DC) são a complicação mais frequente após a substituição da válvula aórtica transcateter (TAVR) e ainda não há consenso sobre seu tratamento.

Objetivo

Avaliar novos DC e implante de marca-passo definitivo (MPD) após a TAVR e avaliar a porcentagem de estimulação ventricular (EV) até 1 ano de acompanhamento.

Métodos

Pacientes submetidos a TAVR de outubro de 2014 a novembro de 2019 foram cadastrados; pacientes com MPD anterior foram excluídos. Dados clínicos, do procedimento, do ECG e do MPD foram coletados até 1 ano após o implante. O nível de significância adotado para a análise estatística foi 0,05%.

Resultados

Um total de 340 indivíduos foram submetidos a TAVR. O DC mais comum foi bloqueio de ramo esquerdo novo (BRE; 32,2%), sendo que 56% destes foram resolvidos após 6 meses. O bloqueio do ramo direito (BRD) foi o maior fator de risco para bloqueio atrioventricular avançado (BAV) [RC=8,46; p<0,001] e implante de MPD [RC=5,18; p<0,001], seguido de BAV de baixo grau prévio [RC=2,25; p=0,016 para implante de MPD]. Em relação às características do procedimento, válvulas de gerações mais recentes e procedimentos de válvula-em-válvula foram associados a menos DC. No total, 18,5% dos pacientes tiveram MPD implantado após a TAVR. Na primeira avaliação do MPD, pacientes com BAV avançado tinham uma porcentagem mediana de EV de 80%, e, após um ano, de 83%. Em relação aos pacientes com BRE e BAV de baixo grau, a EV mediana foi mais baixa (6% na primeira avaliação, p=0,036; 2% após um ano, p = 0,065).

Conclusão

O BRE foi o DC mais frequente após a TAVR, com mais da metade dos casos se resolvendo nos primeiros 6 meses. O BRD foi o principal fator de risco para BAV avançado e implante de MPD. O BAV avançado foi associado a uma porcentagem mais alta de EV no acompanhamento de 1 ano.

Patient-specific multi-scale design optimization of transcatheter aortic valve stents

BACKGROUND AND OBJECTIVE

Transcatheter aortic valve implantation (TAVI) has become the standard treatment for a wide range of patients with aortic stenosis. Although some of the TAVI post-operative complications are addressed in newer designs, other complications and lack of long-term and durability data on the performance of these prostheses are limiting this procedure from becoming the standard for heart valve replacements. The design optimization of these devices with the finite element and optimization techniques can help increase their performance quality and reduce the risk of malfunctioning. Most performance metrics of these prostheses are morphology-dependent, and the design and the selection of the device before implantation should be planned for each individual patient.

METHODS

In this study, a patient-specific aortic root geometry was utilized for the crimping and implantation simulation of 50 stent samples. The results of simulations were then evaluated and used for developing regression models. The strut width and thickness, the number of cells and patterns, the size of stent cells, and the diameter profile of the stent were optimized with two sets of optimization processes. The objective functions included the maximum crimping strain, radial strength, anchorage area, and the eccentricity of the stent.

RESULTS

The optimization process was successful in finding optimal models with up to 40% decrease in the maximum crimping strain, 261% increase in the radial strength, 67% reduction in the eccentricity, and about an eightfold increase in the anchorage area compared to the reference device.

CONCLUSIONS

The stents with larger distal diameters perform better in the selected objective functions. They provide better anchorage in the aortic root resulting in a smaller gap between the device and the surrounding tissue and smaller contact pressure. This framework can be used in designing patient-specific stents and improving the performance of these devices and the outcome of the implantation process.

One-year pacing dependency after pacemaker implantation in patients undergoing transcatheter aortic valve implantation: Systematic review and meta-analysis

Objectives

Atrioventricular conductions disturbances, requiring permanent pacemaker implantation (PPI), represent a potential complication after transcatheter aortic valve implantation (TAVI), However, little is known about the pacemaker dependency after PPI in this patient setting. This systematic review analyses the incidence of PPI, the short-term (1-year) pacing dependency, and predictors for such a state after TAVI.

Methods

We performed a systematic search in PUBMED, EMBASE, and MEDLINE to identify potentially relevant literature investigating PPI requirement and dependency after TAVI. Study data, patients, and procedural characteristics were extracted. Odds ratio (OR) with 95% confidence intervals were extracted.

Results

Data from 23 studies were obtained that included 18,610 patients. The crude incidence of PPI after TAVI was 17% (range, 8.8%-32%). PPI occurred at a median time of 3.2 days (range, 0-30 days). Pacing dependency at 1-year was 47.5% (range, 7%-89%). Self-expandable prosthesis (pooled OR was 2.14 [1.15-3.96]) and baseline right bundle branch block (pooled OR was 2.01 [1.06-3.83]) showed 2-fold greater risk to maintain PPI dependency at 1 year after TAVI.

Conclusions

Although PPI represents a rather frequent event after TAVI, conduction disorders have a temporary nature in almost 50% of the cases with recovery and stabilization after discharge. Preoperative conduction abnormality and type of TAVI are associated with higher PPI dependency at short term.