Long-term outcomes after transcatheter aortic valve implantation: the impact of intraoperative tissue Doppler echocardiography

Safety and feasibility of dobutamine stress echocardiography in symptomatic high gradient aortic stenosis patients scheduled for transcatheter aortic valve implantation

PURPOSE

We aimed to study the safety and feasibility of low-dose dobutamine stress echocardiography in a symptomatic high gradient aortic stenosis population scheduled for transfemoral transcatheter aortic valve implantation (TAVI) and to quantify left ventricular (LV) flow reserve.

METHODS

Fifty patients underwent dobutamine stress echocardiography with 5 minutes increments of 5 μg/kg/min up to 20 μg/kg/min until the heart rate increased ≥20 beats/min from baseline or exceeded 100 beats/min. Other criteria for discontinuing the infusion were major adverse events: ventricular arrhythmia, persistent supraventricular arrhythmia, pulmonary edema, chest pain with significant ST-changes, or minor events: ST-changes, drop in systolic blood pressure >30 mmHg, mild chest pain, and/or dyspnea. LV flow reserve was defined as an increase in stroke volume ≥20% during the test.

RESULTS

Of 50 patients, 45 completed the test according to protocol. No patient had major adverse event. Five patients experienced minor side effects: mild chest pain/dyspnea in three, self-terminating atrial flutter in one, and decrease in blood pressure in one. Significant LV flow reserve was observed in 20 patients (40%).

CONCLUSION

Low-dose dobutamine stress test appeared safe and feasible patients with high gradient aortic stenosis, and showed LV flow reserve in a minority of them.

The learning curve in transcatheter aortic valve implantation clinical studies: A systematic review

Background

Transcatheter aortic-valve implantation (TAVI) has become an essential alternative to surgical aortic-valve replacement in the treatment of symptomatic severe aortic stenosis, and this procedure requires technical expertise. The aim of this study was to identify prospective studies on TAVI from the past 10 years, and then to analyze the quality of information reported about the learning curve.

Materials and methods

A systematic review of articles published between 2007 and 2017 was performed using PubMed and the EMBASE database. Prospective studies regarding TAVI were included. The quality of information reported about the learning curve was evaluated using the following criteria: mention of the learning curve, the description of a roll-in phase, the involvement of a proctor, and the number of patients suggested to maintain skills.

Results

A total of sixty-eight studies met the selection criteria and were suitable for analysis. The learning curve was addressed in approximately half of the articles (n = 37, 54 percent). However, the roll-in period was mentioned by only eight studies (12 percent) and with very few details. Furthermore, a proctorship was disclosed in three articles (4 percent) whereas twenty-five studies (37 percent) included authors that were proctors for manufacturers of TAVI.

Conclusion

Many prospective studies on TAVI over the past 10 years mention learning curves as a core component of successful TAVI procedures. However, the quality of information reported about the learning curve is relatively poor, and uniform guidance on how to properly assess the learning curve is still missing.