Aortic root widening: “pro et contra”

In patients with a small aortic annulus, the clinical benefits of aortic valve replacement depend on avoidance of patient-prosthesis mismatch as it is associated with reduced overall survival. Aortic root widening or enlargement is a useful technique to implant larger valve prosthesis to prevent patient-prosthesis mismatch. Posterior annular enlargement is the commonest technique used for aortic root enlargement. Consistent enlargement of the aortic root requires more extensive procedures like Manouguian or Konno-Rastan techniques. The patients commonly selected are younger patients with good life expectancy. However, caution is advised in applying this procedure in elderly patients, patients with heavily calcified annulus and when performing concomitant procedures. There is no definitive conclusion on the best material to use for the reconstruction of aortic annulus and aorta in aortic root enlargement procedures.

Enlargement of the narrow aortic root: Fear of what?

Prosthesis-patient mismatch (PPM) associated with aortic valve replacement, especially of aortic stenosis, is a common problem. Severe PPM is known to increase perioperative morbidity and mortality and to negatively affect late survival. Surgical enlargement of the narrow aortic root enlargement (ARE) is now increasingly accepted as a method of facilitating implantation of a larger valve prosthesis, hence decreasing the risk of PPM. There are diagnostic methods and tables that help to predict the risk of this complication and assist in the planning of the surgery. Still, many surgeons are afraid or reluctant to perform ARE because of potential technical complications of a procedure perceived to increase the complexity of the surgery. However, these procedures have been proven safe and effective, and are at the reach of almost any cardiac surgeon, including less experienced ones. In addition, there are modifications to the techniques that make them even simpler and more reproducible.

Impact of Aortic Annulus Enlargement on the Outcomes of Aortic Valve Replacement: A Meta-analysis

We sought to evaluate the impact of surgical aortic annulus enlargement (ARE) on the perioperative outcomes of surgical aortic valve replacement. Databases were searched for articles published by October 2019 in order to carry out a systematic review followed by meta-analysis. Thirteen studies with 40,447 patients (aortic valve replacement [AVR] with aortic annulus enlargement [AAE]: 4686 patients; AVR without AAE: 35,761 patients) were included. The total rate of AAE was 11.6%, ranging from 4.1%-28.1%. The overall unadjusted odds ratio (OR) (95% confidence interval [CI]) for operative mortality showed a statistically significant difference between the groups, with higher risk in the "AVR with AAE" group (OR 1.388; 95% CI 1.049-1.836, P < 0.001), but not for isolated AVR+AAE (OR 1.341; 95% CI 0.920-1.956, P = 0.127) and also not in matched populations (OR 1.003; 95% CI 0.773-1.300, P = 0.984). The "AVR with AAE" group showed an overall lower risk of significant patient-prosthesis mismatch (PPM) (OR 0.567; 95% CI 0.376-0.854, P = 0.007) and a higher overall difference in means of indexed effective orifice area (iEOA) (random effect model: 0.058 cm²/m²; 95% CI 0.024-0.092, P < 0.001). The overall ORs for myocardial infarction, stroke, complete heart block/permanent pacemaker implantation and reoperation for bleeding showed no statistically significant difference between the groups. AAE is a useful adjunct to AVR, but the benefit of reduced PPM must be balanced against a possibly higher risk of perioperative mortality.

Prosthesis-Patient Mismatch after Surgical Aortic Valve Replacement: Neither Uncommon nor Harmless

Prosthesis-patient mismatch (PPM) after surgical aortic valve replacement (SAVR) is an issue that has been overlooked (not to say neglected). Cardiac surgeons must bear in mind that this is a real problem that we must tackle. The purpose of this paper is to be a wake-up call to the surgical community by giving a brief overview of what PPM is, its incidence and impact on the outcomes. We also discuss the increasing role played by imaging for predicting and assessing PPM after SAVR (with which surgeons must become more acquainted) and, finally, we present some options to avoid PPM after the surgical procedure.

Aortic root enlargement to mitigate patient-prosthesis mismatch: do early adverse events justify reluctance?†

OBJECTIVES:

Concomitant aortic root enlargement (ARE) at the time of surgical aortic valve replacement can be performed to avoid patient-prosthesis mismatch, an important predictor of adverse long-term outcome.

METHODS:

We performed a single-centre, retrospective analysis of 4120 patients receiving isolated aortic valve replacement, of whom 171 (4%) had concomitant ARE between January 2005 and December 2015. The analysis of postoperative outcome and early mortality was performed. Owing to inequality of the groups, patients were matched 1:1.

RESULTS:

The mean age of all 4120 patients was 68.8 ± 10.5 years, and comorbidities were equally balanced after matching. The mean aortic cross-clamp time, cardiopulmonary bypass time and total operative time were prolonged by 19, 20 and 27 min in the ARE group, respectively. Early mortality was not statistically significantly different with 1.4% in the surgical aortic valve replacement and 1.8% in the ARE group. Postoperative complications were <5% in all matched 338 patients: bleeding (3% vs 3%), pericardial effusion (3.0% vs 4.2%), sternal instability (1.8% vs 0%) and sternal wound infection (3.0% vs 1.2%). A significant higher number of patients had respiratory failure after ARE (unmatched: 17.1% vs 9.9%, P < 0.001; matched: 18.3% vs 9.5%, P = 0.028). Factors independently associated with overall mortality were age [hazard ratio (HR) 1.71], chronic obstructive pulmonary disease (HR 1.47), diabetes (HR 1.82), atrial fibrillation (HR 2.14) and postoperative respiratory failure (HR 2.84).

CONCLUSIONS:

ARE can be performed safely in experienced centres with no significant increase in the risk of early postoperative surgical complications and early mortality. However, the surgeon and the intensive care unit team should be aware of an increased risk for postoperative respiratory failure in ARE patients.

Surgical Enlargement of the Aortic Root Does Not Increase the Operative Risk of Aortic Valve Replacement

Background:

Surgical aortic root enlargement (ARE) during aortic valve replacement (AVR) allows for larger prosthesis implantation and may be an important adjunct to surgical AVR in the transcatheter valve-in-valve era. The incremental operative risk of adding ARE to AVR has not been established. We aimed to evaluate the early outcomes of patients undergoing AVR with or without ARE.

Methods:

From January 1990 to August 2014, 7039 patients underwent AVR (AVR+ARE, n=1854; AVR, n=5185) at a single institution. Patients with aortic dissection and active endocarditis were excluded. Mean age was 65±14 years and 63% were male. Logistic regression and propensity score matching were used to adjust for unbalanced variables in group comparisons.

Results:

Patients undergoing AVR+ARE were more likely to be female (46% versus 34%, P <0.001) and had higher rates of previous cardiac surgery (18% versus 12%, P <0.001), chronic obstructive pulmonary disease (5% versus 3%, P =0.004), urgent/emergent status (6% versus 4%, P =0.01), and worse New York Heart Association status ( P <0.001). Most patients received bioprosthetic valves (AVR+ARE: 73.4% versus AVR: 73.3%, P =0.98) and also underwent concomitant cardiac procedures (AVR+ARE: 68% versus AVR: 67%, P =0.31). Mean prosthesis size implanted was slightly smaller in patients requiring AVR+ARE versus AVR (23.4±2.1 versus 24.1±2.3, P <0.001). In-hospital mortality was higher after AVR+ARE (4.3% versus 3.0%, P =0.008), although when the cohort was restricted to patients undergoing isolated aortic valve replacement with or without root enlargement, mortality was not statistically different (AVR+ARE: 1.7% versus AVR: 1.1%, P =0.29). After adjustment for baseline characteristics, AVR+ARE was not associated with an increased risk of in-hospital mortality when compared with AVR (odds ratio, 1.03; 95% confidence interval, 0.75–1.41; P =0.85). Furthermore, AVR+ARE was not associated with an increased risk of postoperative adverse events. Results were similar if propensity matching was used instead of multivariable adjustments for baseline characteristics.

Conclusions:

In the largest analysis to date, ARE was not associated with increased risk of mortality or adverse events. Surgical ARE is a safe adjunct to AVR in the modern era.