Continuous or interrupted pledgeted suture technique in stented bioprosthetic aortic valve replacement: a comparison of in-hospital outcomes

BACKGROUND

There is ambiguity in the literature regarding the continuous suture technique (CST) for aortic valve replacement (AVR). At our center, there has been a gradual shift towards CST over the interrupted pledgeted technique (IPT). This study aims at comparing outcomes for both techniques.

METHODS

We performed a retrospective analysis of a single-center study of patients undergoing AVR between January 2011 and July 2020. Patients were divided into two groups: Continuous suture technique and interrupted pledget-reinforced sutures. The pre-operative and In-hospital clinical characteristics and echocardiographic hemodynamics (i.e. transvalvular gradients and paravalvular leakage) were compared between CST and IPT.

RESULTS

We compared 791 patients with CST to 568 patients with IPT (median age: 73 and 74 years, respectively, p = 0.02). In CST there were 35% concomitant procedure vs. 31% in IPT (p = 0.16). Early mortality was 3.2% in CST versus 4.8% in IPT (p = 0.15), and a second cross-clamp due to a paravalvular-leak in 0.5% vs. 1.2%, respectively (p = 0.22). The CST was not associated with new-onset conduction-blocks mandating pacemaker implants(OR 1.07, 95% CI 0.54-2.14; P = 0.85). The postoperative gradients on echocardiography were lower in CST compared to IPT, especially in smaller annuli (peak gradients: 15.7mmHg vs. 20.5mmHg, in valve size < 23 mm, p < 0.001).

CONCLUSIONS

The continuous suture technique was associated with lower postoperative gradients and shorter cross-clamp time compared to interrupted pledgeted technique. Differences in paravalvular leaks were non-significant, although slightly less in the continuous suture technique. There were no further differences in valve-related complications. Hence, continues suture technique is safe, with better hemodynamics compared to the interrupted pledgeted technique. This may be of clinical importance, especially in smaller size annular size.

Reliability of in vitro microleakage tests: a literature review

PURPOSE

The literature contains conflicting data about in vitro microleakage evaluations and their usefulness and reliability. No standardization has yet been established. Here we consider features of published studies that might affect the results of the in vitro microleakage tests.

MATERIALS AND METHODS

We reviewed 144 in vitro microleakage studies, published in 14 international reviews between 1992 and 1998, which comprised 917 sets or groups of experiments. The published studies were entered in a database and compared using selected literature criteria: sample, cavities, restoration procedures, thermocycling and mechanical cycling, evaluation method.

RESULTS

The methods employed vary widely. The most frequent methodological choices (%) were (1) specimen storage after extraction: duration (unspecified, 59.2), medium (distilled or deionized water, 33.8), temperature (unspecified, 52.2), additives (none, 47.0); (2) aging method (79.1): duration before aging (< 24 h, 35.9); medium and temperature of storage before aging (distilled or deionized water, 26.8; 37 degrees C, 54.3); (3) medium of cycling (tap water, 50.5), number of cycles ([250-500], 34.6), number of baths (2, 84.0), bath temperature (5 degrees C to 55 degrees C, 60.6), immersion dwell time (30 s, 44.3); (4) tracer: type (basic fuchsin, 40.7), time of immersion (after thermocycling and/or mechanical cycles, 64.1), immersion duration (basic fuchsin: 24 h, 59.5); assessment of dye penetration of sections (91.7): direction (perpendicular, 88.5), number (1, 47.1).

CONCLUSION

The great variability in the methods used in these 144 studies prevented meta-analysis and comparison of the results, thus reducing the value of these methods.