Annals of cardiothoracic surgery最新文献

Background: The labeled sizes of surgical valve prostheses and their discordance with the physical internal valve orifice sizes has long been a controversy in the cardiac surgery community, leading many to believe it to be a contributing factor in prosthesis-patient mismatch following valvular replacement surgery. In an attempt to address this issue, the International Organization for Standardization (ISO) 5840-2:2021 standard for surgical valve prostheses recommends that a new sizing parameter, namely, the effective orifice diameter, be provided in labeling by all manufacturers as an indicator of the true flow-passing capacity of a prosthetic valve.

Methods: The ISO Cardiac Valves Working Group conducted a multi-laboratory round-robin study to investigate whether the effective orifice diameter of a prosthetic surgical valve could be derived repeatably and reproducibly through steady forward-flow testing. A total of seven valve models, each with multiple sizes, were tested, including a mechanical heart valve and multiple biological heart valves.

Results: The round-robin study confirmed that the steady forward-flow test had good intra-laboratory repeatability and inter-laboratory reproducibility in deriving the effective orifice diameters of surgical valve prostheses. On average, among the participating laboratories, the experimentally derived effective orifice diameter of a prosthetic heart valve was 3-12 mm smaller than its labeled size.

Conclusions: The effective orifice diameter provides better characterization of the hydrodynamic characteristics of a surgical valve prosthesis and can be derived using a validated steady forward-flow test method. This new sizing parameter will soon be adopted by surgical valve manufacturers and provided in device labeling to inform valve selection by surgeons.

Background: The desire of patients to avoid anticoagulation, together with the potential of valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR), have resulted in the increasing use of bioprosthetic valves for aortic valve replacement (AVR). While patient-prosthesis mismatch (PPM) is known to be an adverse risk after AVR, few studies have addressed the effect of PPM on valve durability. This study evaluates the role of valve size and hemodynamics on long term durability after AVR with a Magna bioprosthesis.

Methods: We performed a retrospective, single-center evaluation of patients who underwent a surgical AVR procedure between June 2004 through December 2022 using the Magna bioprosthesis. Perioperative information and long-term follow-up data were sourced from the institution's Society for Thoracic Surgeons Adult Cardiac Surgery Registry and outcomes database. Cumulative incidence of freedom from reintervention were estimated accounting for competing events. Group comparisons used Gray's test.

Results: Among 2,100 patients, the mean patient age was 69 years (range, 22-95 years), of whom 98% had native aortic valve disease, 32.5% had concomitant coronary bypass grafting, and 19% had mitral valve surgery. Median follow-up was 5.8 (1.9-9.4) years, during which 116 reinterventions were performed, including 74 explants and 42 VIV procedures. Nine hundred and twenty-eight patients died prior to reintervention. Incidence of all cause reintervention was 1.2%, 4.5%, and 11.7% at 5, 10, and 15 years, respectively. Smaller valve size was associated with worse survival (P<0.001), but not with reintervention. Higher mean gradient at implant was associated with increased late reintervention [sub-distribution hazard ratio: 1.016; 95% confidence interval (CI): 1.005 to 1.028; P=0.0047, n=1,661].

Conclusions: While reintervention rates are low for the Magna prosthesis at 15 years, the analysis is confounded by the competing risk of death. PPM, as reflected physiologically by elevated post-operative valve gradients, portends an increased risk of intervention. Further study is necessary to elucidate the mechanism of early stenosis in patients who progress to reintervention.

For decades, surgeons have recognized the risk of prosthesis-patient mismatch (PPM) when treating aortic stenosis (AS) with surgical aortic valve replacement (SAVR). The concept of PPM-or placing a valve that is too small for the cardiac output requirements of the patient-has been associated with worse patient outcomes, including increased risk of death. Transcatheter aortic valve replacement (TAVR) has become the standard treatment for most patients with severe symptomatic AS and is associated with improved hemodynamics and lower risks of PPM. Larger surgical valves, stentless, and sutureless technology, and surgical aortic annulus enlargement (AAE) have been employed to avoid severe PPM. However, especially in the small aortic annulus (SAA), TAVR may provide a benefit. Understanding who is at risk for PPM requires preplanning, and cardiac-gated computed tomography (CT) imaging is the standard of care when considering TAVR. It should be standard for all patients with AS. Once SAA is identified, the risk of PPM can be calculated, and an informed decision made on whether to proceed with SAVR or TAVR. In the current TAVR era, younger patients are treated with TAVR driven by patient preference, but with little long-term data to support the practice. Selecting the best valve for the patient is a multifactorial decision often nuanced by anatomical considerations, hemodynamic and durability expectations, and decisions regarding lifetime management that may include placing a second valve. Although PPM may be only one of the factors to consider, the association with elevated mean gradients and worse outcomes certainly makes TAVR a good solution for many patients.

Prosthesis-patient mismatch (PPM) occurs when the effective orifice area (EOA) of a normally functioning prosthetic valve is too small in relation to the patient's body size. The effect of PPM on outcomes and valve durability have gained credibility, making this an important possibly preventable risk factor. Transcatheter aortic valve replacement (TAVR) generally has a lower incidence of PPM than surgical aortic valve replacement (SAVR). Current surgical literature and randomized trials show an association between severe PPM and mortality in patients with SAVR but there is less evidence for an association with TAVR. Differences in the incidence of PPM may be related to the methods and cutoffs for measuring mismatch. This review will discuss the current state of field and propose standardization of measurement methods which may more accurately risk stratify patients.

Background: There is mounting evidence at experienced centers that aortic annular enlargement (AAE) procedures are safe adjuncts to surgical aortic valve replacement (SAVR) that do not increase perioperative morbidity and mortality. This systematic review and meta-analysis aims to assess the impact of AAE procedures on mid-term outcomes after SAVR.

Methods: OVID MEDLINE, OVID Embase, and Cochrane Library were searched comprehensively. Comparative studies examining adult patients undergoing SAVR with and without AAE were eligible for inclusion. Studies involving aortic root replacement, Ross procedures, and Ozaki procedures were excluded. The risk of bias was assessed according to Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I), and the quality of evidence was evaluated according to Grading of Recommendations Assessment, Development and Evaluation (GRADE). Random effects meta-analysis facilitated the quantitative synthesis.

Results: A total of 2,765 records were retrieved. After full-text review, 15 eligible studies were identified for data extraction and synthesis. The dataset included a total of 216,654 patients (AAE: 7,967; no AAE: 208,687). Only mid-term outcomes were available. In unmatched and unadjusted studies, perioperative mortality was noted to be higher in the AAE group. However, this difference was not observed in studies with matching or adjusted outcomes. In both the unmatched and unadjusted studies, and the matched and adjusted studies, there were no statistically significant differences identified regarding perioperative stroke, myocardial infarction, or permanent pacemaker implantation. Similarly, there were no statistically significant differences identified in mid-term mortality [hazard ratio (HR), 1.03; 95% confidence interval (CI): 0.95 to 1.11; P=0.49; I²=20% (matched/adjusted studies)], aortic valve reintervention [HR, 0.98; 95% CI: 0.75 to 1.27; P=0.86; I²=0% (matched/adjusted studies)], or heart failure [HR, 1.06; 95% CI: 0.86 to 1.30; P=0.58; I²=25% (matched/adjusted studies)].

Conclusions: SAVR with AAE does not appear to be associated with increased perioperative morbidity or mortality. There is no conclusive indication that AAE enhances mid-term survival, freedom from reoperation, or freedom from heart failure after SAVR.

In 1978, Rahimtoola published a successful series of surgical aortic valve replacements (SAVR) on patients with severe aortic stenosis (AS) with congestive heart failure (CHF). He described the perfect prosthesis-patient match as a "prosthetic valve with a functioning opening area that matches the patient's normal functioning valve." This manuscript revisits the forty-six-year journey in pursuit of that perfect match. We address the essential components for the perfect match, such as the usefulness of the current valve sizing techniques using the manufacturer's labeled valve size (MLVS) and sizer, the accuracy of an objective parameter to define the perfect match, and the need and safety to enlarge the patient's annulus and root to accommodate the proper size valve. A thorough literature search was performed using the University of Michigan Medical Library search engine. The population included patients who underwent SAVR. Three individual searches were conducted: (I) valve size and sizing techniques; (II) hemodynamic performance (HP) and prosthesis-patient mismatch (PPM); and (III) aortic root enlargement (ARE) procedures. Excluded were articles not in English, articles that involved animal research, duplicate articles, articles involving valve repair, allograft or autograft replacement, and articles specific to aortic sizing and congenital heart surgery. The emphasis was placed on randomized prospective trials, large registry trials with and without propensity matching, and meta-analysis articles. We discovered that the manufacturer-labeled valve size and sizing technique does not accurately represent the functional opening area of the valve. A pre-operative multidetector computed tomography (CT) scan is an accurate and reproducible method for measuring patient root and annulus dimensions and should be used for pre-operative valve sizing for SAVR. Matching the CT area derived aortic diameter with the true functional diameter of the opening of the prosthetic valve will yield the best prosthesis-patient match. ARE is safe and should be used to attain the best match.

Atrial fibrillation (AF) has been reported as a major cause of cardiac morbidity and mortality, and significantly reduces the quality of life in symptomatic patients. Current guidelines recommend antiarrhythmic drugs and catheter ablation (CA) as first-line therapy. Despite CA showed to be associated with lower incidence of peri-procedural complications, rhythm outcomes are far from optimal. Indeed, patients undergoing CA frequently require multiple AF ablation procedures, especially in those with persistent and long-standing persistent AF. While surgical ablation can provide transmural lesions, surgical invasiveness has limited the widespread use of this approach due to the increased perioperative complications. The development of minimally invasive thoracoscopic approaches has renewed the interest towards surgical ablation, thus favoring more simplified ablation sets. Therefore, the concept of "hybrid" ablation has emerged in order to theoretically enhance advantages of both minimally invasive and CA procedures while seeking to improve rhythm outcomes and reduce invasiveness and incidence of perioperative complications. On one hand, it provides the effectiveness of a surgical ablation, on the other, electrical mapping during CA can identify and treat any ablation gap or provide additional ablation lines, thus improving the chance of a stable sinus rhythm restoration at long-term follow-up. Three main thoracoscopic strategies are currently available. All of them can be performed in conjunction with the "catheter ablation procedure": the "Fusion" technique, the bipolar clamp technique, and the most recent "convergent" technique. CA can be performed either simultaneously or with a staged approach after a blanking period in order to allow the ablation lesion to stabilize. Excellent results of the hybrid procedures have been reported in terms of rhythm outcomes and incidence of perioperative complications. This narrative review aims to discuss the rationale behind the concept of hybrid ablation for the treatment of AF regarding different available strategies, results and expert opinions.