Rate Control versus Rhythm Control for Atrial Fibrillation after Cardiac Surgery.

BACKGROUND: Atrial fibrillation after cardiac surgery is associated with increased rates of death, complications, and hospitalizations. In patients with postoperative atrial fibrillation who are in stable condition, the best initial treatment strategy--heart-rate control or rhythm control--remains controversial. METHODS: Patients with new-onset postoperative atrial fibrillation were randomly assigned to undergo either rate control or rhythm control. The primary end point was the total number of days of hospitalization within 60 days after randomization, as assessed by the Wilcoxon rank-sum test. RESULTS: Postoperative atrial fibrillation occurred in 695 of the 2109 patients (33.0%) who were enrolled preoperatively; of these patients, 523 underwent randomization. The total numbers of hospital days in the rate-control group and the rhythm-control group were similar (median, 5.1 days and 5.0 days, respectively; P=0.76). There were no significant between-group differences in the rates of death (P=0.64) or overall serious adverse events (24.8 per 100 patient-months in the rate-control group and 26.4 per 100 patient-months in the rhythm-control group, P=0.61), including thromboembolic and bleeding events. About 25% of the patients in each group deviated from the assigned therapy, mainly because of drug ineffectiveness (in the rate-control group) or amiodarone side effects or adverse drug reactions (in the rhythm-control group). At 60 days, 93.8% of the patients in the rate-control group and 97.9% of those in the rhythm-control group had had a stable heart rhythm without atrial fibrillation for the previous 30 days (P=0.02), and 84.2% and 86.9%, respectively, had been free from atrial fibrillation from discharge to 60 days (P=0.41). CONCLUSIONS: Strategies for rate control and rhythm control to treat postoperative atrial fibrillation were associated with equal numbers of days of hospitalization, similar complication rates, and similarly low rates of persistent atrial fibrillation 60 days after onset. Neither treatment strategy showed a net clinical advantage over the other. (Funded by the National Institutes of Health and the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT02132767.).

Effect of Cerebral Embolic Protection Devices on CNS Infarction in Surgical Aortic Valve Replacement: A Randomized Clinical Trial.

Importance: Stroke is a major complication of surgical aortic valve replacement (SAVR). Objective: To determine the efficacy and adverse effects of cerebral embolic protection devices in reducing ischemic central nervous system (CNS) injury during SAVR. Design, Setting, and Participants: A randomized clinical trial of patients with calcific aortic stenosis undergoing SAVR at 18 North American centers between March 2015 and July 2016. The end of follow-up was December 2016. Interventions: Use of 1 of 2 cerebral embolic protection devices (n = 118 for suction-based extraction and n = 133 for intra-aortic filtration device) vs a standard aortic cannula (control; n = 132) at the time of SAVR. Main Outcomes and Measures: The primary end point was freedom from clinical or radiographic CNS infarction at 7 days (± 3 days) after the procedure. Secondary end points included a composite of mortality, clinical ischemic stroke, and acute kidney injury within 30 days after surgery; delirium; mortality; serious adverse events; and neurocognition. Results: Among 383 randomized patients (mean age, 73.9 years; 38.4% women; 368 [96.1%] completed the trial), the rate of freedom from CNS infarction at 7 days was 32.0% with suction-based extraction vs 33.3% with control (between-group difference, -1.3%; 95% CI, -13.8% to 11.2%) and 25.6% with intra-aortic filtration vs 32.4% with control (between-group difference, -6.9%; 95% CI, -17.9% to 4.2%). The 30-day composite end point was not significantly different between suction-based extraction and control (21.4% vs 24.2%, respectively; between-group difference, -2.8% [95% CI, -13.5% to 7.9%]) nor between intra-aortic filtration and control (33.3% vs 23.7%; between-group difference, 9.7% [95% CI, -1.2% to 20.5%]). There were no significant differences in mortality (3.4% for suction-based extraction vs 1.7% for control; and 2.3% for intra-aortic filtration vs 1.5% for control) or clinical stroke (5.1% for suction-based extraction vs 5.8% for control; and 8.3% for intra-aortic filtration vs 6.1% for control). Delirium at postoperative day 7 was 6.3% for suction-based extraction vs 15.3% for control (between-group difference, -9.1%; 95% CI, -17.1% to -1.0%) and 8.1% for intra-aortic filtration vs 15.6% for control (between-group difference, -7.4%; 95% CI, -15.5% to 0.6%). Mortality and overall serious adverse events at 90 days were not significantly different across groups. Patients in the intra-aortic filtration group vs patients in the control group experienced significantly more acute kidney injury events (14 vs 4, respectively; P = .02) and cardiac arrhythmias (57 vs 30; P = .004). Conclusions and Relevance: Among patients undergoing SAVR, cerebral embolic protection devices compared with a standard aortic cannula did not significantly reduce the risk of CNS infarction at 7 days. Potential benefits for reduction in delirium, cognition, and symptomatic stroke merit larger trials with longer follow-up. Trial Registration: clinicaltrials.gov Identifier: NCT02389894.

The impact of perioperative stroke and delirium on outcomes after surgical aortic valve replacement.

OBJECTIVE: The effects of stroke and delirium on postdischarge cognition and patient-centered health outcomes after surgical aortic valve replacement (SAVR) are not well characterized. Here, we assess the impact of postoperative stroke and delirium on these health outcomes in SAVR patients at 90 days. METHODS: Patients (N = 383) undergoing SAVR (41% received concomitant coronary artery bypass graft) enrolled in a randomized trial of embolic protection devices underwent serial neurologic and delirium evaluations at postoperative days 1, 3, and 7 and magnetic resonance imaging at day 7. Outcomes included 90-day functional status, neurocognitive decline from presurgical baseline, and quality of life. RESULTS: By postoperative day 7, 25 (6.6%) patients experienced clinical stroke and 103 (28.5%) manifested delirium. During index hospitalization, time to discharge was longer in patients experiencing stroke (hazard ratio, 0.62; 95% confidence interval [CI], 0.42-0.94; P = .02) and patients experiencing delirium (hazard ratio, 0.68; 95% CI, 0.54-0.86; P = .001). At day 90, patients experiencing stroke were more likely to have a modified Rankin score >2 (odds ratio [OR], 5.9; 95% CI, 1.7-20.1; P = .01), depression (OR, 5.3; 95% CI, 1.6-17.3; P = .006), a lower 12-Item Short Form Survey physical health score (adjusted mean difference -3.3 ± 1.9; P = .08), and neurocognitive decline (OR, 7.8; 95% CI, 2.3-26.4; P = .001). Delirium was associated with depression (OR, 2.2; 95% CI, 0.9-5.3; P = .08), lower 12-Item Short Form Survey physical health (adjusted mean difference -2.3 ± 1.1; P = .03), and neurocognitive decline (OR, 2.2; 95% CI, 1.2-4.0; P = .01). CONCLUSIONS: Stroke and delirium occur more frequently after SAVR than is commonly recognized, and these events are associated with disability, depression, cognitive decline, and poorer quality of life at 90 days postoperatively. These findings support the need for new interventions to reduce these events and improve patient-centered outcomes.

Impact of Aortic Atherosclerosis Burden on Outcomes of Surgical Aortic Valve Replacement.

BACKGROUND: Epiaortic ultrasound detects and localizes ascending aortic atherosclerosis. In this analysis we investigated the association between epiaortic ultrasound-based atheroma grade during surgical aortic valve replacement (SAVR) and perioperative adverse outcomes. METHODS: SAVR patients in a randomized trial of 2 embolic protection devices underwent a protocol-defined 5-view epiaortic ultrasound read at a core laboratory. Aortic atherosclerosis was quantified with the Katz atheroma grade, and patients were categorized as mild (grade I-II) or moderate/severe (grade III-V). Multivariable logistic regression was used to estimate associations between atheroma grade and adverse outcomes, including death, clinically apparent stroke, cerebral infarction on diffusion-weighted magnetic resonance imaging, delirium, and acute kidney injury (AKI) by 7 and 30 days. RESULTS: Precannulation epiaortic ultrasound data were available for 326 of 383 randomized patients (85.1%). Of these, 106 (32.5%) had moderate/severe Katz atheroma grade at any segment of the ascending aorta. Although differences in the composite of death, stroke, or cerebral infarction on diffusion-weighted magnetic resonance imaging by 7 days were not statistically significant, moderate/severe atheroma grade was associated with a greater risk of AKI by 7 days (adjusted odds ratio, 2.63; 95% confidence interval, 1.24-5.58; P = .01). At 30 days, patients with moderate/severe atheroma grade had a greater risk of death, stroke, or AKI (adjusted odds ratio, 1.97; 95% confidence interval, 1.04-3.71; P = .04). CONCLUSIONS: Moderate/severe aortic atherosclerosis was associated with an increased risk of adverse events after SAVR. Epiaortic ultrasound may serve as a useful adjunct for identifying patients who may benefit from strategies to reduce atheroembolic complications during SAVR.

Epicardial ultrasonic ablation of atrial fibrillation during concomitant cardiac surgery is a valid option in patients with ischemic heart disease.

BACKGROUND: Surgical therapy of atrial fibrillation concomitant to coronary bypass grafting using epicardial Ultrasound technology was assessed after a minimum 6-month follow-up. METHODS AND RESULTS: A cohort of 98 consecutive patients with a mean age of 72+/-7.58 years and a primary diagnosis of ischemic heart disease had surgery for structural disease. Coronary artery bypass grafting was isolated (n=51) or associated (n=47) with various combinations of aortic, mitral, tricuspid, and left ventricular restoration surgery. Atrial fibrillation duration ranged from 6 to 360 months (mean 71 months) and was permanent in 47 patients, paroxysmal in 34, and persistent in 17. Left atrial mean diameter was 48+/-6.71 mm. A circumferential ablation was performed off-pump, before the concomitant procedure, and was always associated with an epicardial mitral line lesion using the same technology. At 3-, 6-, and 12-month visits, patients were routinely evaluated by physical examination, ECG, chest X-ray, and 24-hour Holter. There were 1 early death (1%) and 4 extracardiac late deaths. A pacemaker was implanted in 4 patients. Mean follow-up time was 325 days, 2 patients being lost to follow-up. Freedom from atrial fibrillation and flutter at the 6-month visit was 84% for the entire population, 76% in patients with permanent, and 91% in patients with paroxysmal atrial fibrillation. At the 1-year visit, 85% were free from atrial fibrillation or flutter. CONCLUSIONS: Epicardial beating heart ablation using therapeutic ultrasound is safe, reliable, and can easily treat atrial fibrillation in a difficult surgical population of patients with primary ischemic heart disease.

Midterm, multicenter clinical and hemodynamic results for the Trifecta aortic pericardial valve.

OBJECTIVE: To evaluate the midterm hemodynamic performance and clinical outcomes of the Trifecta aortic pericardial valve. METHODS: In a multicenter, prospective, nonrandomized, follow-up study, 710 patients underwent surgical implantation of a pericardial stented aortic prosthesis (Trifecta valve; St Jude Medical, St. Paul, Minn). The valve is constructed from bovine pericardium mounted externally onto a titanium stent. Subjects were followed on an annual basis over 6 years. RESULTS: Operations were performed from 2007 to 2009, and mean age was 72.4 ± 9.3 years; 471 of 710 (66.3%) were men. Preoperatively, 361 of 710 (50.8%) of patients were in New York Heart Association class III or IV, and at 6 years postoperatively, 92 of 96 (95.8%) were New York Heart Association class I or II. Six years postoperatively, average mean gradient across all valve sizes was 11.0 mm Hg, and the average effective orifice area index was 0.80 cm2/m2. The proportion of patients without moderate-to-severe valvular regurgitation at 6 years was 95.2% (80/84). Six years postoperatively, freedom from valve-related mortality, nonstructural dysfunction, and paravalvular leak were 98.3%, 98.6%, and 98.9%, respectively, and freedom from reoperation due to structural valve deterioration was 97.3% (95% confidence limits, 98.6-94.7). CONCLUSION: These midterm results demonstrate that the Trifecta valve is a safe and effective valve substitute with excellent hemodynamic performance and durability that is maintained through the 6-year follow-up period.

Is Surgical Intervention the Optimal Therapy for the Treatment of Aortic Valve Stenosis for Patients With Intermediate Society of Thoracic Surgeons Risk Score?

BACKGROUND: Patients at intermediate risk (IR) according to The Society of Thoracic Surgeons risk score are today frequently oriented toward the transfemoral aortic valve replacement (TAVR) option. Our goal was to evaluate the best treatment strategies for IR patients with severe aortic stenosis. METHODS: Of a consecutive series of 1,144 surgical aortic valve replacements (AVRs) performed in our institution between 2008 and 2014, we reviewed the early and late outcomes of two different groups: a low-risk (LR) group of 470 patients, and an IR group of 620. We eliminated from the analysis 54 high-risk patients who were currently candidates for TAVR. All patients underwent surgical AVR with or without concomitant coronary artery bypass grafting. Social Security database interrogation provided long-term information. RESULTS: The early mortality rate (30 days) between LR and IR patients was similar (1.70% vs 2.74%, p = 0.25) and both lower than predicted mortality rates. However, cumulative 5-year survival was significantly higher in LR patients (86.3%) than in IR patients (75.4%; p = 0.0007 by log-rank test), although excellent in IR group. Comparing IR survivors and nonsurvivors, ages at operation were 69.5 ± 12.7 years for survivors vs 75.4 ± 9.6 years for those experiencing late deaths (p = 0.002). Risk factors for late deaths after multivariate analysis were age, hemodialysis, and chronic lung disease. CONCLUSIONS: Most IR patients today should undergo surgical AVR, but because of survival rates combined with still unavailable late structural deterioration rates in TAVR valves, patients in the IR group with high Society of Thoracic Surgeons scores and known risk factors may be better served with TAVR as data regarding late percutaneous valve function accrue.

The effect of postoperative medical treatment on left ventricular mass regression after aortic valve replacement.

OBJECTIVE: The study objective was to analyze factors associated with left ventricular mass regression in patients undergoing aortic valve replacement with a newer bioprosthesis, the Trifecta valve pericardial bioprosthesis (St Jude Medical Inc, St Paul, Minn). METHODS: A total of 444 patients underwent aortic valve replacement with the Trifecta bioprosthesis from 2007 to 2009 at 6 US institutions. The clinical and echocardiographic data of 200 of these patients who had left ventricular hypertrophy and follow-up studies 1 year postoperatively were reviewed and compared to analyze factors affecting left ventricular mass regression. RESULTS: Mean (standard deviation) age of the 200 study patients was 73 (9) years, 66% were men, and 92% had pure or predominant aortic valve stenosis. Complete left ventricular mass regression was observed in 102 patients (51%) by 1 year postoperatively. In univariate analysis, male sex, implantation of larger valves, larger left ventricular end-diastolic volume, and beta-blocker or calcium-channel blocker treatment at dismissal were significantly associated with complete mass regression. In the multivariate model, odds ratios (95% confidence intervals) indicated that male sex (3.38 [1.39-8.26]) and beta-blocker or calcium-channel blocker treatment at dismissal (3.41 [1.40-8.34]) were associated with increased probability of complete left ventricular mass regression. Patients with higher preoperative systolic blood pressure were less likely to have complete left ventricular mass regression (0.98 [0.97-0.99]). CONCLUSIONS: Among patients with left ventricular hypertrophy, postoperative treatment with beta-blockers or calcium-channel blockers may enhance mass regression. This highlights the need for close medical follow-up after operation. Labeled valve size was not predictive of left ventricular mass regression.

Suture technique does not affect hemodynamic performance of the small supra-annular Trifecta bioprosthesis.

OBJECTIVE: The study objective was to evaluate whether aortic valve replacement with the Trifecta valve (St Jude Medical Inc, St Paul, Minn) using simple sutures produces better hemodynamic performance than valve replacement with noneverting pledget-reinforced sutures. METHODS: We analyzed prospectively acquired 1-year hemodynamic data of patients with small aortic annulus sizes who were enrolled in a multicenter trial of the Trifecta aortic valve bioprosthesis and underwent aortic valve replacement with a 19-mm or 21-mm bioprosthesis between August 2007 and November 2009. We compared preoperative clinical information and 1-year postoperative hemodynamic data for noneverting pledget-reinforced sutures (group 1) versus everting mattress sutures or simple sutures (group 2). RESULTS: A total of 346 patients underwent aortic valve replacement: 269 in group 1 and 77 in group 2. Preoperative demographic characteristics for the 2 groups were similar. For groups 1 and 2, the mean gradient was 10.4±4.7 mm Hg and 11.1±4.4 mm Hg for 19-mm valves, respectively, and 8.4±3.5 mm Hg and 8.8±3.6 mm Hg for 21-mm valves, respectively; the effective orifice area was 1.40 cm2 and 1.25 cm2 for 19-mm valves, respectively, and 1.57 cm2 and 1.50 cm2 for 21-mm valves, respectively. The rate of severe prosthesis-patient mismatch (indexed effective orifice area≤0.65 cm2/m2) was 18.6% (n=11) and 25% (n=6) for 19-mm valves, respectively, and 10.9% (n=20) and 16.3% (n=8) for 21-mm valves, respectively. CONCLUSIONS: The suture method did not affect hemodynamic performance of supra-annular bioprostheses in patients with small aortic annulus sizes. Choice of suture technique should be determined by surgeon experience and local anatomic features.

The St Jude Medical Trifecta aortic pericardial valve: results from a global, multicenter, prospective clinical study.

BACKGROUND: The St Jude Medical Inc (St Paul, Minn) Trifecta valve is a novel aortic biological prosthesis that incorporates several design features, including a true supra-annular sewing cuff, a stent design that maximizes valve hemodynamics while minimizing leaflet stresses, and an ethanol-based anticalcification technology. This study establishes the safety and early clinical and hemodynamic performance of the Trifecta valve. METHODS: The Trifecta bioprosthesis was implanted in 1014 eligible patients between 2007 and 2009 at 31 centers. The mean age of the population was 72.5 ± 9.0 years, of whom 650 (64.1%) were male and 364 (35.9%) were female. Eighty-two subjects (8.1%) had undergone previous open surgery. Indications for aortic valve replacement surgery included stenosis in 556 patients (54.8%), regurgitation in 61 patients (6.0%), and mixed pathology in 397 patients (39.2%). RESULTS: The overall follow-up included 844.3 late patient-years. Early (≤ 30 day) mortality occurred in 18 patients (1.8%), and there were 23 late (≥ 31 days) deaths yielding a linearized mortality rate of 2.72% per late patient-year. There were 27 early thromboembolic events, including 8 (0.8%) strokes, 17 (1.7%) reversible neurologic events, and 2 (0.2%) systemic embolic events. There were no instances of early valve thrombosis, endocarditis, or clinically significant hemolysis. There were 16 late thromboembolic events (linearized rate of 1.90% per year of follow-up), including 4 strokes and 12 reversible neurologic events. In total, there were 5 late valve explants, including 1 structural deterioration and 4 prosthetic valve endocarditis cases. Overall, freedom from valve explant was 99.4% at 2 years. At the time of discharge, average mean gradients ranged from 9.3 to 4.1 mm Hg and effective orifice area ranged from 1.58 to 2.50 cm(2) for valve sizes 19 to 29 mm, respectively. CONCLUSIONS: The St Jude Medical Trifecta valve is a unique pericardial bioprosthesis with design elements that provide excellent hemodynamic performance while providing ease of implantation. Long-term follow-up continues to confirm the promising results of this innovative bioprosthesis.

Reproducibility of left atrial ablation with high-intensity focused ultrasound energy in a calf model.

OBJECTIVE: Achieving transmural tissue ablation might be necessary for successful treatment of atrial fibrillation. The purpose of this study was to evaluate the reproducibility of transmural left atrial ablation using a high-intensity focused ultrasound energy system in a calf model. METHODS: Nine heparinized bovines underwent a beating-heart left atrial ablation with a single application of the high-intensity focused ultrasound device. All animals were acutely killed, and the left atrium was fixed in formalin. Protocolized histological sections (5 µm) were obtained throughout each lesion and prepared with Masson trichrome and hematoxylin and eosin staining. Measurements were performed on a total of 359 slides from the 9 lesions. In addition, fresh left atrial tissues from 18 unused human donor hearts that did not meet the criteria for cardiac transplantation were measured at the site where the high-intensity focused ultrasound device is normally applied. RESULTS: Calf left atrial thickness ranged between 2.5 and 20.1 mm, with a mean of 9.10 mm. High-intensity focused ultrasound ablation consistently produced a 100% transmural lesion in left atrial thickness up to 6 mm. In addition, a transmural lesion was observed in 91% of tissues that were up to 10 mm thick and in 85% that were up to 15 mm thick. Human left atrial thickness ranged between 1.2 to 6 mm, with a mean of 3.7 mm. CONCLUSIONS: Calf left atrial thickness in this study was greater than human left atrial thickness. Human left atrial thickness is generally less than 6 mm, and in this range high-intensity focused ultrasound ablation achieved 100% transmurality. These histological results might correlate with a high success rate of atrial fibrillation ablation by using the high-intensity focused ultrasound system.

Ultrasonic cardiac ablation for atrial fibrillation during concomitant cardiac surgery: long-term clinical outcomes.

BACKGROUND: Therapeutic ultrasound as an alternative to the maze procedure was evaluated in this large US experience. Safety and efficacy were assessed at 6-, 12-, and 18-month visits with systematic 24-hour Holter monitoring. METHODS: From February 2005 to February 2007, 220 patients were prospectively enrolled in a single center study, and among them 129 patients with concomitant cardiac surgery and at least 6-month follow-up were reviewed. Primary procedures were mitral surgery in 50% of the cases, coronary bypass in 32%, and aortic surgery in 16%. Atrial fibrillation was permanent in 66 (51.1%), paroxysmal in 43 (33.3%), and persistent in 20 (15.5%) patients. An epicardial and circumferential left atrial encircling line was created on the beating heart. Routinely a mitral isthmus line was also created from the left atrium epicardium using an ultrasonic handheld device. RESULTS: No morbidity or mortality was device-related. There were four (2.33%) early deaths and six late extra-cardiac deaths. Follow-up ranged from 6 to 670 days with a mean follow-up of 358.5 days, median 340 days with two patients lost to follow-up. Freedom from atrial fibrillation or left-sided flutter was 83.2%, 84.4%, and 86.2% at 6, 12, and 18 months, respectively. A pacemaker was implanted in seven patients (5.4%). Male gender and left atrial dimension were significant risk factors for failure. CONCLUSIONS: The study confirms the excellent safety record of the technology, and the efficacy at the level reported in a previous European multicenter study. Efficacy is also maintained at longer (12 and 18 months) follow-up.