Hemodynamic Comparison of the On-X and Top Hat Mechanical Aortic Valve Prostheses.

BACKGROUND: There are limited data comparing hemodynamic valve function in mechanical aortic valve prostheses. We compared the hemodynamic function of two commonly used mechanical aortic valve (AV) prostheses, the On-X and Top Hat valves. METHODS: Retrospective analysis of 512 patients who received AV replacement with On-X (n=252, 49%) or Top Hat (n=260, 51%) mechanical valves between 2011 and 2019. Patients were matched based on select variables. Echocardiographic data were collected pre- and postoperatively over a median follow-up of 1.39 years. RESULTS: A total of 320 patients were matched, 160 patients in each group. Despite being matched for left ventricular outflow tract diameter, patients in the Top Hat group received a greater prevalence of smaller tissue annulus diameter valves (≤ 21 mm) (83% versus 38%; P<0.001). Patients in the On-X group had longer aortic cross-clamp time (78 versus 64 minutes; P<0.001) during isolated aortic valve replacement. Discharge echocardiography showed no difference in the AV area index between both groups (1.00 versus 1.02 cm2/m2; P=0.377). During longer-term echocardiographic follow-up, AV area index remained stable for both valves within their respective tissue annulus diameter groups (P=0.060). CONCLUSIONS: There was no difference between the two valves with respect to the AV area index at discharge, and hemodynamic function was stable during longer-term follow-up. The longer aortic cross-clamp time observed in the On-X group may indicate increased complexity in implantation compared to the Top Hat group.

Outcomes of aortic surgery in patients with Takayasu arteritis.

OBJECTIVE: To investigate the presentation, aortic involvement, and surgical outcomes in patients with Takayasu arteritis undergoing aortic surgery. METHODS: We queried our surgical database for patients with Takayasu arteritis who underwent aortic surgery from 1994 to 2022. RESULTS: There were a total of 31 patients with Takayasu arteritis who underwent aortic surgery. Patients' median age at the time of diagnosis was 35.0 years (interquartile range, 25.0-42.0). The majority were female (n = 27, 87.0%). Most patients (n = 28, 90.3%) were diagnosed before surgery, and 3 patients (9.6%) were diagnosed perioperatively. The median time interval from diagnosis to surgery was 2.8 years (interquartile range, 0.5-13.9). The most common presentation was ascending aorta aneurysm (n = 22, 70.9%), and severe aortic regurgitation was the most common valve insufficiency (n = 17, 54.8%). The most common operation was ascending aorta replacement (n = 20, 64.5%), and aortic valve replacement was the most common valve intervention (n = 17, 54.8%). Active vasculitis was identified in 2 (11.7%) aortic valve specimens. Early mortality was 6.5% (n = 2). A total of 6 deaths occurred over a median follow-up of 13.1 years (interquartile range, 6.1-25.2). Survival at 10 years was 86.7% (95% CI, 75.4-99.7). A total of 5 patients (16.1%) required a subsequent operation in a median of 1.9 years (interquartile range, 0.2-7.4). Freedom from reoperation was 96.9% (95% CI, 90.1-100) at 1 year, 89.4% (95% CI, 78.7-100.0) at 5 years, and 77.5% (95% CI, 61.2-98.1) at 10 and 15 years. CONCLUSIONS: Ascending aorta aneurysm and aortic valve regurgitation are the most frequent presentations in patients with Takayasu arteritis requiring aortic surgery. Surgery in these individuals is safe, with acceptable short- and long-term results.

Post-mortem examination of fatal acute type A aortic dissection: what does it teach us?

OBJECTIVES: Acute type A aortic dissection (ATAAD) remains a highly life-threatening condition. This study investigates factors associated with fatal ATAAD prior to surgical treatment. METHODS: We reviewed autopsy reports of ATAAD decedents who died before surgical intervention and underwent postmortem examination at our clinic from 1994 to 2022. RESULTS: Among 94 eligible cases, 50 (53.2%) decedents had DeBakey type I dissection, and 44 (46.8%) had DeBakey type II dissection. Most were males, 63 (67%), and 72 (77%) had a history of hypertension. The median age was 70.5 years, and the type II group was a decade older than the type I group (P < 0.001). Decedents in the type II group predominantly died during the first hour after symptoms onset 16 (52%), while in the type I group, fatalities occurred between 1 h and 1 day, 27 (66%). The most common site of the intimal tear was the midportion of the ascending aorta, 45 (48%). The median ascending aorta size was 5 cm for the entire cohort, 5.2 cm for type I and 4.6 cm for type II (P < 0.045). CONCLUSIONS: In this autopsy study of fatal acute aortic dissection, the median aortic size was below the current guideline threshold for elective repair. Type II acute aortic dissections were found more frequently than expected and were characterized by older age, advanced aortic atherosclerosis, smaller aortic size, a shorter interval from symptom onset to death and a higher frequency of syncope compared to type I dissection.

Benefit of Anticoagulation Early After Surgical Aortic Valve Replacement Using Bioprosthetic Valves.

OBJECTIVE: To compare all-cause mortality and thromboembolic events in patients undergoing surgical aortic valve replacement (sAVR) receiving anticoagulation with warfarin versus patients with no systemic anticoagulation. PATIENTS AND METHODS: Using data from the OptumLabs Data Warehouse, we investigated adult patients having bioprosthetic sAVR with or without coronary artery bypass from January 1, 2007, through December 31, 2019. Patients were classified into groups of nonwarfarin or warfarin (≥30 days of continuous prescription coverage after sAVR). One-to-one propensity score (PS) matching was used to adjust for group differences. RESULTS: Of 10,589 patients having sAVR, 7659 (72.3%) were in the nonwarfarin group and 2930 (27.7%) were in the warfarin group. After PS matching, 2930 pairs of patients were analyzed. Median follow-up was 4.1 months (interquartile range [IQR], 2.6-7.4 months) for the warfarin group and 21.3 months (IQR, 7.8-24.0 months) for the nonwarfarin group. Overall mortality was lower for the warfarin group than for the nonwarfarin group (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.47 to 1.00; P=.047), and there was a trend toward decreased cumulative incidence of thromboembolic events (subdistribution HR [SHR], 0.62; 95% CI, 0.35 to 1.07; P=.09). Cumulative incidence of major bleeding events was higher for the warfarin group vs the nonwarfarin group (SHR, 1.94; 95% CI, 1.28 to 2.94; P=.002). Results were similar in a subgroup analysis of patients undergoing isolated sAVR. CONCLUSION: During the prescription coverage period, warfarin use after bioprosthetic sAVR was associated with lower all-cause mortality and decreased risk of thromboembolism compared with not receiving warfarin. However, warfarin use was associated with an increased risk of major bleeding events.

Fate of concomitant tricuspid regurgitation in patients undergoing coronary artery bypass grafting.

OBJECTIVE: Owing to a lack of supportive data, tricuspid regurgitation (TR) is usually not addressed in patients undergoing coronary artery bypass grafting (CABG). Here we evaluated changes in TR degrees over time and its impact on survival in patients undergoing CABG. METHODS: We reviewed the data of 9726 patients who underwent isolated CABG between January 2000 and January 2021. According to preoperative TR severity, patients were stratified into nonsignificant (none to trivial, mild) and significant (moderate to severe) TR groups. We excluded patients who had undergone previous tricuspid valve surgery, pacemaker placement, and concomitant valve or ablative surgery. Propensity score matching and Cox proportional hazards models were used to identify associations between TR grade and the primary outcome of all-cause mortality. The secondary outcome was change in TR severity on the last echocardiogram. RESULTS: After propensity score matching, 380 patients in each group were identified. At baseline, 359 patients had moderate TR (94.5%) and 21 (5.5%) had severe TR. On the last follow-up echocardiogram, TR had improved in 40.5% of the patients in the significant TR group. Kaplan-Meier survival curves showed significantly lower survival in patients with significant preoperative TR compared to those with nonsignificant TR (P < .001). After adjusting for other confounders, survival was no worse in the patients with significant TR group (hazard ratio, 1.05; 95% confidence interval, 0.80-1.38; P = .70). CONCLUSIONS: Significant preoperative TR improved in 40.5% of patients after isolated CABG. After adjusting for other factors, significant TR did not affect long-term survival.

Impact of atrial fibrillation on outcomes in asymptomatic severe aortic stenosis: a propensity-matched analysis.

Background: Atrial fibrillation (AF) portends poor prognosis in patients with aortic stenosis (AS). Objectives: This study aimed to study the association of AF vs. sinus rhythm (SR) with outcomes in asymptomatic severe AS during routine clinical practice. Methods: We identified 909 asymptomatic patients from 3,208 consecutive patients with aortic valve area ≤1.0 cm2 and left ventricular ejection fraction ≥50% at a tertiary academic center. Patients were grouped by rhythm at the time of transthoracic echocardiogram [SR: 820/909 (90%) and AF: 89/909 (10%)]. Propensity-matched analyses (2 SR:1 AF) matching 174 SR to 89 AF patients by age, sex, and clinical comorbidities were used to compare outcomes. Results: In the propensity-matched cohort, median age (82 ± 8 vs. 81 ± 9 years, p = 0.31), sex distribution (male 58% vs. 52%, p = 0.30), and Charlson comorbidity index (4.0 vs. 3.0, p = 0.26) were not different in AF vs. SR. Median follow-up duration was 2.6 (IQR: 1.0-4.4) years. The 1-year rate of aortic valve replacement (AVR) was not different (AF: 32% vs. SR: 37%, p = 0.31). All-cause mortality was higher in AF [hazard ratio (HR): 1.68 (1.13-2.50), p = 0.009]. Independent predictors of mortality were age [HR: 1.92 (1.40-2.62), p < 0.001], Charlson comorbidity index [1.09 (1.03-1.15), p = 0.002], aortic valve peak velocity [HR: 1.87 (1.20-2.94), p = 0.006], stroke volume index [HR: 0.75 (0.60-0.93), p = 0.01], moderate or more mitral regurgitation [HR: 2.97 (1.43-6.19), p = 0.004], right ventricular systolic dysfunction [HR: 2.39 (1.29-4.43), p = 0.006], and time-dependent AVR [HR: 0.36 (0.19-0.65), p = 0.0008]. There was no significant interaction of AVR and rhythm (p = 0.57). Conclusions: Lower forward flow, right ventricular systolic dysfunction, and mitral regurgitation identified increased risk of subsequent mortality in asymptomatic patients with AF and AS. Additional studies of risk stratification of asymptomatic AS in AF vs. SR are needed.

Diagnosis and surgical management of pericardial constriction after cardiac surgery.

OBJECTIVES: Previous cardiac surgery is an increasingly common etiology of constrictive pericarditis, but there is a paucity of data on clinical presentation and outcome of surgical treatment. METHODS: We reviewed data of 263 patients who underwent pericardiectomy for postoperative constriction from January 1, 1993, through July 1, 2017. Outcomes of interest were early and late mortality, as well as features of clinical presentation. RESULTS: Median patient age was 64 (56-72) years, and the median interval between previous operation and pericardiectomy was 2.7 years (range, 0-54 years). Previous operations included coronary artery bypass grafting in 114 (43%), valve surgery in 85 (32%), combined coronary artery bypass grafting and valve surgery in 33 (13%), and other procedures in 31 (12%). Common presentations were symptoms of right heart failure in 221 (84%) or dyspnea in 42 (16%). Moderate-to-severe tricuspid valve regurgitation was present in 108 (41%) patients. There were 14 (5.5%) deaths within 30 days postoperatively, and survival at 5 and 10 years postoperatively was 61% and 44%. On multivariate analysis, older age (P = .013), diabetes (P = .019), and nonelective pericardiectomy within 2 years of cardiac surgery (P < .001) were associated with decreased long-term survival. CONCLUSIONS: Pericardial constriction after cardiac surgery can present at any interval postoperatively. Symptoms and signs of right heart failure in patients with previous cardiac surgery should alert physicians to the possibility of pericardial constriction followed by a correct diagnosis. Pericardiectomy performed urgently following cardiac operation has poor long-term outcomes.

Medium-Term Outcomes of the Different Antithrombotic Regimens After Transcatheter Aortic Valve Implantation.

Bioprosthetic valve thrombosis is associated with accelerated bioprosthesis degeneration and valve re-replacement. Whether 3-month warfarin use after transcatheter aortic valve implantation (TAVI) protects against such consequences is unknown. We aimed to investigate if 3-month warfarin treatment after TAVI is associated with better outcomes than dual antiplatelet therapy (DAPT) and single antiplatelet therapy (SAPT) at medium-term follow-up. Adults who underwent TAVI were identified retrospectively (n = 1,501) and classified into warfarin, DAPT, and SAPT groups based on antithrombotic regimen received. Patients with atrial fibrillation were excluded. Outcomes and valve hemodynamics were compared between the groups. Annualized change from baseline in mean gradients and effective orifice area at last follow-up echocardiography was calculated. Overall, 844 patients were included (mean age: 80 ± 9 years, 43% women; 633 receiving warfarin, 164 DAPT, and 47 SAPT). Median time to follow-up was 2.5 (interquartile range 1.2 to 3.9) years. There were no differences in the adjusted outcome end points of ischemic stroke, death, valve re-replacement/intervention, structural valve degeneration, or their composite end point at follow-up. Annualized change in aortic valve area was significantly higher in DAPT (-0.11 [0.19] cm2/year) than warfarin (-0.06 [0.25] cm2/y, p = 0.03), but annualized change in mean gradients was not different (p >0.05). In conclusion, antithrombotic regimen, including warfarin, after TAVI was associated with marginally lower decrease in aortic valve area but no difference in medium-term clinical outcomes compared with DAPT and SAPT.

Prediction of permanent pacemaker implantation after transcatheter aortic valve replacement: The role of machine learning.

BACKGROUND: Atrioventricular block requiring permanent pacemaker (PPM) implantation is an important complication of transcatheter aortic valve replacement (TAVR). Application of machine learning could potentially be used to predict pre-procedural risk for PPM. AIM: To apply machine learning to be used to predict pre-procedural risk for PPM. METHODS: A retrospective study of 1200 patients who underwent TAVR (January 2014-December 2017) was performed. 964 patients without prior PPM were included for a 30-d analysis and 657 patients without PPM requirement through 30 d were included for a 1-year analysis. After the exclusion of variables with near-zero variance or ≥ 50% missing data, 167 variables were included in the random forest gradient boosting algorithm (GBM) optimized using 5-fold cross-validations repeated 10 times. The receiver operator curve (ROC) for the GBM model and PPM risk score models were calculated to predict the risk of PPM at 30 d and 1 year. RESULTS: Of 964 patients included in the 30-d analysis without prior PPM, 19.6% required PPM post-TAVR. The mean age of patients was 80.9 ± 8.7 years. 42.1 % were female. Of 657 patients included in the 1-year analysis, the mean age of the patients was 80.7 ± 8.2. Of those, 42.6% of patients were female and 26.7% required PPM at 1-year post-TAVR. The area under ROC to predict 30-d and 1-year risk of PPM for the GBM model (0.66 and 0.72) was superior to that of the PPM risk score (0.55 and 0.54) with a P value < 0.001. CONCLUSION: The GBM model has good discrimination and calibration in identifying patients at high risk of PPM post-TAVR.

Obesity and vascular complication in percutaneous transfemoral transcatheter aortic valve insertion.

BACKGROUND: Obesity has been associated with an increased risk of vascular complication during percutaneous coronary intervention, but there are no data on the risk of vascular complication during percutaneous transfemoral transcatheter aortic valve insertion (TAVI). OBJECTIVES: We hypothesized there would be a similar increased risk associated with TAVI. METHODS: We reviewed the records of 1176 patients who received percutaneous transfemoral transcatheter aortic valve insertion from September 2015 to September 2020. All patients received 1) preoperative computed tomoraphy angiography assessment of the abdomen and pelvis to delineate iliofemoral artery anatomy, 2) ultrasound-guided percutaneous femoral arterial access, and 3) pre-closure of the delivery sheath femoral access site. Vascular complication was recorded based on definitions set forth by Valve Academic Research Consortium 3. RESULTS: The median age of patients was 81 years, and 60% were men. The median body mass index (BMI) was 29 kg/m2 (range, 11-67), and 91 (8%) patients had a value ≥40 kg/m2 (i.e., morbid obesity). Delivery sheath size was 14-French in 859 (73%) patients, 16-French in 311 (26%), and 18-French in 6 (1%). Vascular complication occurred in 53 (5%) patients, including 39 (7%) among the first half of procedures and 14 (2%) among the second half (p < 0.001). When stratified by obesity status (BMI < or ≥30 kg/m2 , p < 0.001), the complication rate was 4% in nonobese patients and 5% in obese patients. Multivariable analysis showed no overall association between risk of vascular complication and BMI categories (p = 0.583)BMI continuous values (p = 0.529), or sheath size (p = 0.217). CONCLUSIONS: Obesity is not associated with a vascular complication during percutaneous transfemoral transcatheter aortic valve insertion. The operation should not be denied in obese patients.

The interaction of forced expiratory volume in 1 s and N-terminal pro-B-type natriuretic peptide with outcomes after transcatheter aortic valve replacement.

OBJECTIVES: Low forced expiratory volume in 1 s (FEV1) and elevated N-terminal pro-B-type natriuretic peptide (NT-Pro-BNP) have been individually associated with poor outcomes after transcatheter aortic valve replacement (TAVR). We hypothesized a combination of the 2 would provide prognostic indication after TAVR. METHODS: We categorized 871 patients who received TAVR from 2008 to 2018 into 4 groups according to baseline FEV1 (<60% or ≥60% predicted) and NT-Pro-BNP (<1601 or ≥1601 pg/ml): group A (n = 312, high FEV1, low NT-Pro-BNP), group B (n = 275, high FEV1, high NT-Pro-BNP), group C (n = 123 low FEV1, low NT-Pro-BNP) and group D (n = 161, low FEV1, high NT-Pro-BNP). The primary end point was survival at 1 and 5 years. RESULTS: Patients in group A had more severe aortic stenosis and achieved the best long-term survival at 1 [93% (95% CI: 90-96)] and 5 [45.3% (95% CI: 35.4-58)] years. Low FEV1 and high NT-Pro-BNP (group D) patients had more severe symptoms, higher Society of Thoracic Surgeons predicted risk of operative mortality, lower ejection fraction and aortic valve gradient at baseline. Patients in group D had the worst survival at 1 [76% (95% CI: 69-83)] and 5 years [13.1% (95% CI: 7-25)], hazard ratio compared to group A: 2.29 (95% CI: 1.6-3.2, P < 0.001) with 25.7% of patients in New York Heart Association class III-IV. Patients in groups B and C had intermediate outcomes. CONCLUSIONS: The combination of FEV1 and NT-Pro-BNP stratifies patients into 4 groups with distinct risk profiles and clinical outcomes. Patients with low FEV1 and high NT-Pro-BNP have increased comorbidities, poor functional outcomes and decreased long-term survival after TAVR.

Impact of Atrial Fibrillation on Outcomes in Very Severe Aortic Valve Stenosis.

The prevalence and impact of atrial fibrillation (AF) versus sinus rhythm (SR) on outcomes in very severe aortic stenosis (vsAS) of the native valve is unknown. The aim of the study was to determine the prognostic significance of AF in vsAS. A total of 563 patients with vsAS (transaortic valve peak velocity ≥5 m/s) and left ventricular ejection fraction ≥50% were identified retrospectively. Patients were divided by rhythm at the time of index transthoracic echocardiogram (AF: n = 50 [9%] vs SR: n = 513 [91%]). Patients with AF were older (83.1 ± 7.5 vs 72.5 ± 12.2 y, p <0.001) and had no difference in gender distribution (p = 0.49) but had a higher Charlson co-morbidity index (2 [1,3] vs 1 [0,2], p = 0.01). There was no difference in transaortic peak velocity (5.3 ± 0.3 m/s vs 5.4 ± 0.4 m/s, p = 0.13) and left ventricular ejection fraction was comparable (63 ± 7 vs 66 ± 7%, p = 0.01). Age-, gender-, Charlson co-morbidity index-, and time-dependent aortic valve replacement (AVR)-adjusted overall mortality at 5 years was significantly higher in patients with AF than patients with SR (hazard ratio [HR] 1.88 [1.23 to 2.85], p = 0.003). AVR was associated with improved survival (HR = 0.30 [0.22 to 0.42], p <0.001), with no statistically significant interaction of AVR and rhythm (p = 0.36). Outcomes were also compared in the 2 SR:1 AF propensity-matched analyses (100 SR: 50 AF), with matching done according to age, gender, clinical co-morbidities, and year of echocardiogram. In the propensity-matched analysis, age-, gender-, and time-dependent AVR-adjusted all-cause mortality was higher in AF (HR 2.32 [1.41 to 3.82], p <0.001). In conclusion, AF was not uncommon in vsAS and identified a subset of patients at a much higher risk of mortality without AVR.

The subtle tine: Asymptomatic Micra perforation incidentally discovered during cardiac surgery.

A 70-year-old woman with longstanding persistent atrial fibrillation underwent Micra leadless pacemaker implantation and atrioventricular nodal ablation. No postprocedural complications were noted. She subsequently underwent surgical mitral valve replacement 4 years later. During the surgery, Micra tine perforation of the right ventricular free wall was seen. No device revision was performed due to her asymptomatic status and stable pacemaker position/function. Pericardial effusion is a known complication of Micra implantation. The incidence of tine perforation is unknown as many patients may be asymptomatic. The clinical consequences regarding adverse events, device functionality, and explantation/extraction risk profile remain to be determined.

Aortic root replacement in the setting of a mildly dilated nonsyndromic ascending aorta.

OBJECTIVE: There is controversy on how to address mild aortic root dilation during concomitant aortic valve replacement: composite aortic valve conduit replacement or separate ascending aorta and aortic valve replacement. We reviewed our experience to address the issue. METHODS: We retrospectively reviewed 778 adult nonsyndromic patients with aortic root diameter 55 mm or less who received replacement of the ascending aorta and aortic valve from January 1994 to June 2017. Patients were divided into 2 groups based on the type of aortic root intervention: composite aortic valve conduit replacement in 406 patients (52%) and separate ascending aorta and aortic valve replacement in 372 patients (48%). Propensity matching was used to mitigate differences in baseline patient characteristics and produced 188 matched pairs. RESULTS: Sinus of Valsalva diameter was 43 mm (39-47). Operative mortality occurred in 3 patients (2%) in the composite aortic valve conduit replacement group and in 5 patients (3%) in the separate ascending aorta and aortic valve replacement group (P = .470). Median follow-up was 9.6 years (8.4-10.1). Long-term mortality was similar in the 2 groups (P = .083). Repeat operation was performed in 13 patients (7%) in the composite aortic valve conduit replacement group and in 19 patients (10%) in the separate ascending aorta and aortic valve replacement group (P = .365). Sinus of Valsalva diameter decreased 2 mm (-4-0; median follow-up 41 months) in the propensity-matched separate ascending aorta and aortic valve replacement group. CONCLUSIONS: In patients with mild aortic root dilation, separate ascending aorta and aortic valve replacement results in a similar risk of repeat operation and mortality in comparison with composite aortic valve replacement. Separate ascending aorta and aortic valve replacement is not associated with subsequent aortic root dilation on medium-term echocardiography follow-up.

Anticoagulation After Bioprosthetic Aortic Valve Replacement: Are We Following the Guidelines?

BACKGROUND: Guideline-directed medication adherence is considered an important quality measure after cardiac surgery. We evaluated compliance with the American College of Cardiology/American Heart Association guidelines for warfarin use after surgical aortic valve replacement (sAVR) using bioprostheses and examined potential variations in anticoagulation practice over time. METHODS: Using the OptumLabs Data Warehouse, we investigated adult patients having bioprosthetic sAVR with or without coronary artery bypass (2007-2019). Early postoperative warfarin use was defined as ≥30 days of continuous prescription coverage after sAVR. RESULTS: Among 10 730 adult patients having sAVR, 3071 (28.6%) received warfarin early postoperatively. Median length of warfarin prescription coverage was 4.5 months (interquartile range, 3.0-8.9 months). However, only 11.1% (736/6634) had warfarin prescription coverage of 3 to 6 months in compliance with the most recent guidelines. Yearly warfarin prescription rate did not change significantly during the 13-year period (P = .386). Compared with patients from the non-warfarin group, those receiving warfarin prescriptions were older and more likely to be male and to have atrial fibrillation, congestive heart failure, chronic pulmonary disease, and CHA2DS2-VASc score ≥2; warfarin use was also greater in patients receiving prescriptions for other cardiac medications (P < .05). CONCLUSIONS: Anticoagulation after sAVR as reflected by warfarin prescriptions may be underused; the rates of warfarin use have not changed in the last decade. Although additional studies are needed to confirm the benefit of early anticoagulation after sAVR, these results indicate that guideline recommendations are not followed by most clinicians. The findings highlight a potentially important area for quality improvement.

Underestimation of Aortic Stenosis Severity by Doppler Mean Gradient during Atrial Fibrillation: Insights from Aortic Valve Weight.

BACKGROUND: Doppler mean gradient (MG) can underestimate aortic stenosis (AS) severity when obtained during atrial fibrillation (AF) compared with sinus rhythm (SR). Aortic valve weight (AVW) is a flow-independent measure of AS severity. The objective of this study was to determine whether AVW or AVW/MG ratio was increased in AF versus SR in patients with AS. METHODS: Excised native aortic valves from 495 consecutive patients (median age, 77 years; interquartile range [IQR], 71-82 years; 40% women), with left ventricular ejection fractions ≥50% who underwent surgical aortic valve replacement for native valve severe AS (aortic valve area ≤ 1 cm2 or indexed aortic valve area ≤ 0.6 cm2/m2) were weighed. Excised AVW/MG ratios were compared in AF versus SR in patients with high-gradient AS (aortic peak velocity ≥ 4 m/sec or MG ≥ 40 mm Hg) and low-gradient AS (aortic peak velocity < 4 m/sec and MG < 40 mm Hg) in sex-specific analyses. RESULTS: AF was present in 51 patients (10%; 11 of 51 [22%] had low-gradient AS) and SR in 444 (90%; 23 of 444 [5%] had low-gradient AS). There was no difference in sex distribution between AF and SR. Aortic valve area was not different, but forward stroke volume index and transaortic valve flow rate were lower in AF (P ≤ .002 for all); MG was lower in AF versus SR (median, 46 mm Hg [IQR, 37-50 mm Hg] vs 50 mm Hg [IQR, 44-61 mm Hg]; P < .0001). Overall AVW was not different (median, 2,290 mg [IQR, 1,830-3,063 mg] vs 2,140 mg [IQR, 1,530-2,958 mg]; P = .31), but overall AVW/MG ratio was higher in AF (median, 55 [IQR, 41-67] vs 42 [IQR, 30-55]; P = .001). In sex- and MG-specific analyses, the AVW/MG ratio was higher in AF compared with SR in men with high-gradient AS (median, 58 [IQR, 41-75] vs 51 [IQR, 39-61]; P = .03), but the differences were not statistically significant between AF and SR in other groups. CONCLUSIONS: AVW was discordant to Doppler MG in AF compared with SR in men with high-gradient AS. Additional studies of the relationship of MG to other measures of AS severity, such as leaflet fibrosis, are needed.

Excess Reintervention With Mitroflow Prosthesis for Aortic Valve Replacement: Ten-Year Outcomes of a Randomized Trial.

BACKGROUND: Current bioprostheses are considered to have improved durability and better hemodynamic performance compared with previous designs, but there are limited comparative data on late outcomes. METHODS: From 2009 through 2011, 300 adults with severe aortic valve stenosis undergoing aortic valve replacement (AVR) were randomly assigned to receive Edwards Magna, St Jude Epic, or Sorin Mitroflow bioprostheses (n = 100, n = 101, n = 99, respectively). Overall survival was analyzed using Kaplan-Meier and Cox proportional hazards methods, whereas competing risk analysis was used for all time-to-event outcomes. Serial echocardiographic data were fitted with longitudinal models stratified by implant valve size. RESULTS: During median follow-up of 9.8 years (interquartile range, 8.7-10.2), 10-year survival was 50% for the Magna group, 42% for the Epic group, and 41% for the Mitroflow group (P = .415). Cumulative risk of stroke was 9% at 10 years, and rates were comparable for the three groups. Indexed aortic valve area and mean gradients were similar among the three groups receiving 19 mm and 21 mm valves, but in larger (23 mm or more) prostheses, gradients were lower (P < .001) and indexed aortic valve areas were higher in the Magna group (P < .001). The 10-year risk of endocarditis differed by group (P = .033), with higher incidence in the Mitroflow vs the Magna group (7% vs 0%, P = .019). Late risk of reinterventions in the Mitroflow group was 22%, compared with 0% in the Magna group (P < .001) and 5% in the Epic group (P = .008). CONCLUSIONS: The Magna valve had the lowest gradients and largest indexed aortic valve area with larger implant sizes. The Mitroflow bioprosthesis is associated with an increased rate of reintervention and possible increased risk of infection compared with Magna and Epic valves.