Concomitant surgical ablation for atrial fibrillation is associated with increased risk of acute kidney injury but improved late survival

BACKGROUND

Acute kidney injury (AKI) after cardiac surgery remains a common complication that has been associated with increased morbidity and mortality. This study implemented Kidney Disease Improving Global Outcomes criteria to evaluate renal outcomes after concomitant surgical ablation for atrial fibrillation.

METHODS

Patients with a history of atrial fibrillation who underwent elective cardiac surgery at our institution from 2008 to 2018 were retrospectively reviewed. Those with preoperative renal dysfunction were excluded. Patients were classified as those who underwent concomitant Cox-Maze IV (CMP-IV) (n = 376) or no surgical ablation (n = 498). Nearest neighbor 1:1 propensity matching was conducted on fourteen covariates. AKI was evaluated by mixed effects logistic regression analysis. Long-term survival was evaluated by proportional hazards regression.

RESULTS

Propensity matching yielded 308 patients in each group (n = 616). All preoperative variables were similar between groups. The concomitant CMP-IV group had a greater incidence of AKI: 32% (n = 99) versus 16% (n = 49), P < .001. After accounting for bypass time and nonablation operations on mixed effects analysis, concomitant CMP-IV was associated with increased risk of AKI (odds ratio, 1.89; confidence interval, 1.12-3.18; P = .017). While AKI was associated with decreased late survival (P < .001), patients who received a concomitant CMP-IV maintained superior 7-year survival to patients who received no ablation (P < .001). No patients required permanent dialysis.

CONCLUSIONS

Concomitant CMP-IV was independently associated with increased risk of AKI in the acute postoperative period. However, the long-term risks of AKI were offset by the significant survival benefit of CMP-IV. Concerns regarding new-onset renal dysfunction should not prohibit recommendation of this procedure in appropriate patients.

Impact of Obesity on Atrial Fibrillation Recurrence Following Stand-Alone Cox Maze IV Procedure

OBJECTIVE

Obesity is a strong and independent factor for the development of atrial fibrillation (AF), and adversely impacts the success of catheter ablation procedures for AF. This study evaluated the impact of body mass index (BMI) on the outcomes following surgical ablation of AF.

METHODS

Between 2003 and 2019, 236 patients underwent a stand-alone biatrial Cox maze IV procedure (CMP-IV) for refractory AF. Obesity was defined as BMI ≥30 kg/m². Patients were divided into two groups: BMI <30 kg/m² (n = 100) and BMI ≥30 kg/m² (n = 136). Freedom from atrial tachyarrhythmia (ATA) was determined using electrocardiography, Holter, or pacemaker interrogation at 1 year and annually thereafter. Recurrence was defined as any documented ATA lasting ≥30 s. Predictors of recurrence were determined using multivariable logistic regression. Preoperative and procedural outcomes were compared between groups.

RESULTS

Obese patients had a higher rate of diabetes (16% vs 7%, P = 0.044) and larger left atrial diameter (4.9 ± 1.1 cm vs 4.6 ± 1.0 cm, P = 0.021) when compared to non-obese patients. There was no difference in major complication rate between the groups (4% vs 7%, P = 0.389). There was no operative mortality in either group. During 4.1 ± 2.4 years of follow-up, there was no significant difference in freedom from ATA with or without antiarrhythmic drugs in obese patients when compared to the non-obese group (P > 0.05). Absence of sinus rhythm at discharge predicted AF recurrence up to 7 years postoperatively.

CONCLUSIONS

As opposed to catheter ablation, obesity did not adversely impact the short and long-term outcomes of stand-alone surgical ablation with CMP-IV, and BMI was not a predictor of AF recurrence. Additionally, there was no significant increase in major complications in obese patients.

Efficacy of the stand-alone Cox-Maze IV procedure in patients with longstanding persistent atrial fibrillation

INTRODUCTION

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, and results in significant morbidity and mortality. The Cox-Maze IV procedure (CMP-IV) has been shown to have excellent efficacy in returning patients to sinus rhythm, but there have been few reports of late follow-up in sizable cohorts of patients with longstanding persistent AF, the most difficult type of AF to treat.

METHODS AND RESULTS

Between May 2003 and March 2020, 174 consecutive patients underwent a stand-alone CMP-IV for longstanding persistent AF. Rhythm outcome was assessed postoperatively for up to 10 years, primarily via prolonged monitoring (Holter monitor, pacemaker interrogation, or implantable loop recorder). Fine-Gray regression was used to investigate factors associated with atrial tachyarrhythmia (ATA) recurrence, with death as a competing risk. Median duration of preoperative AF was 7.8 years (interquartile range: 4.0-12.0 years), with 71% (124/174) having failed at least one prior catheter-based ablation. There were no 30-day mortalities. Freedom from ATAs was 94% (120/128), 83% (53/64), and 88% (35/40) at 1, 5, and 7 years, respectively. On regression analysis, preoperative AF duration and early postoperative ATAs were associated with late ATAs recurrence.

CONCLUSION

Despite the majority of patients having a long-duration of preoperative AF and having failed at least one catheter-based ablation, the stand-alone CMP-IV had excellent late efficacy in patients with longstanding persistent AF, with low morbidity and no mortality. We recommend consideration of stand-alone CMP-IV for patients with longstanding persistent AF who have failed or are poor candidates for catheter ablation.

Late results after stand-alone surgical ablation for atrial fibrillation

OBJECTIVES

Stand-alone surgical ablation of atrial fibrillation is indicated in patients with refractory atrial fibrillation who have failed medical or catheter-based ablation. Few reports of late outcomes after stand-alone surgical ablation exist using comprehensive follow-up with strict definitions of success. This study examined our late outcomes of the stand-alone Cox-Maze IV procedure.

METHODS

Between January 2003 and December 2019, 236 patients underwent a stand-alone Cox-Maze IV for refractory atrial fibrillation. Freedom from atrial tachyarrhythmias was assessed by electrocardiography, Holter, or pacemaker interrogation for up to 10 years, with a mean follow-up of 4.8 ± 3.5 years. Rhythm outcomes were compared in multiple subgroups. Factors associated with recurrence were determined using Fine-Gray regression, allowing for death as the competing risk.

RESULTS

The majority of patients (176/236, 75%) had nonparoxysmal atrial fibrillation. Median duration of preoperative atrial fibrillation was 6.2 years (interquartile range, 3-11). Fifty-nine percent of patients (140/236) failed 1 or more prior catheter-based ablation. Thirteen patients (6%) experienced a major complication. There was no 30-day mortality. Freedom from atrial tachyarrhythmias was 94% (187/199), 89% (81/91), and 77% (24/31) at 1, 5, and 10 years, respectively. There was no difference in freedom from atrial tachyarrhythmias between patients with paroxysmal atrial fibrillation versus nonparoxysmal atrial fibrillation (P > .05) or those undergoing sternotomy versus a minimally invasive approach (P > .05). Increased left atrial size and number of catheter ablations were associated with late atrial fibrillation recurrence. For patients who experienced any atrial tachyarrhythmia recurrence, the median number of recurrences was 1.5 (1.0-3.0).

CONCLUSIONS

The stand-alone Cox-Maze IV had excellent late efficacy at maintaining sinus rhythm in patients with symptomatic, refractory atrial fibrillation, with low morbidity and no mortality. The Cox-Maze IV, in contrast to catheter-based ablation, was equally effective in patients with paroxysmal and nonparoxysmal atrial fibrillation.

Massive Left Atrial Thrombus After a Left Atrial Surgical Ablation and Bioprosthetic Mitral Valve Replacement

Variability exists regarding the timing and duration of anticoagulation after surgical ablation for atrial fibrillation and bioprosthetic mitral valve replacement (MVR). We report a case in which a patient developed a massive left atrial (LA) thrombus after MVR and left-sided radiofrequency ablation (LRFA). Despite acutely elevated gradients across the bioprosthetic valve, the patient remained asymptomatic and hemodynamically stable; thus, a multidisciplinary, patient-centered discussion was had and the patient was treated successfully with oral anticoagulation.

Impact of Surgical Experience on Operative Mortality After Reoperative Cardiac Surgery

BACKGROUND

Learning curves and skill attrition with aging have been reported to impair outcomes in select surgical subspecialties, but their role in complex cardiac surgery remains unknown.

METHODS

From 1986 to 2019, 2314 patients underwent reoperative cardiac surgery: coronary artery bypass grafting (n = 543), valve (n = 1527), or combined coronary artery bypass grafting and valve (n = 244). Thirty-four different surgeons in practice between 1 and 39 years were included. Standardized mortality ratio (observed-to-expected) was determined for all surgeons in each post-training year of experience.

RESULTS

Risk-adjusted cumulative sum change-point analysis was used to define five distinct career phases: 0 to 4 years, 5 to 8 years, 9 to 17 years, 18 to 28 years, and 29 to 39 years. With 5 to 8 years and 18 to 28 years of experience, standardized mortality ratio was near unity (0.95 and 1.05, respectively) and lowest with 9 to 17 years of experience (0.78, P = .03). In the youngest experience group (0 to 4 years), observed and expected mortality were both highest, and standardized mortality ratio was elevated at 1.29, which approached statistical significance (P = .059). In the oldest experience group (29 to 39 years), expected mortality was low compared with most other groups but observed mortality increased, yielding a significantly elevated standardized mortality ratio at 1.53 (P = .032).

CONCLUSIONS

Standardized mortality ratios with reoperative cardiac surgery were highest early and late in a surgeon's career and lowest in mid career. As surgeons gain experience, outcomes improve through the first two career decades, then stabilize in the third decade before declining in the fourth decade.

Impact of age on atrial fibrillation recurrence following surgical ablation

OBJECTIVES

The incidence of atrial fibrillation (AF) in patients older than 75 years of age is expected to increase, and its treatment remains challenging. This study evaluated the impact of age on the outcomes of surgical ablation of AF.

METHODS

A retrospective review was performed of patients who underwent the Cox-maze IV procedure at a single institution between 2005 and 2017. The patients were divided into a younger (age <75 years, n = 548) and an elderly cohort (age ≥75 years, n = 148). Rhythm outcomes were assessed at 1 year and annually thereafter. Predictors of first atrial tachyarrhythmia (ATA) recurrence were determined using Fine-Gray regression, allowing for death as the competing risk.

RESULTS

The mean age of the elderly group was 78.5 ± 2.8 years. The majority of patients (423/696, 61%) had nonparoxysmal AF. The elderly patients had a lower body mass index (P < .001) and greater rates of hypertension (P = .011), previous myocardial infarction (P = .017), heart failure (P < .001), and preoperative pacemaker (P = .008). Postoperatively, the elderly group had a greater rate of overall major complications (23% vs 14%, P = .017) and 30-day mortality (6% vs 2%, P = .026). The percent freedom from ATAs and antiarrhythmic drugs was lower in the elderly patients at 3 (69% vs 82%, P = .030) and 4 years (65% vs 79%, P = .043). By competing risk analysis, the incidence of first ATA recurrence was greater in elderly patients (33% vs 20% at 5 years; Gray test, P = .005). On Fine-Gray regression adjusted for clinically relevant covariates, increasing age was identified as a predictor of ATAs recurrence (subdistribution hazard ratio, 1.03; 95% confidence interval, 1.02-1.05, P < .001).

CONCLUSIONS

The efficacy of the Cox-maze IV procedure was worse in elderly patients; however, the majority of patients remained free of ATAs at 5 years. The lower success rate in these greater-risk patients should be considered when deciding to perform surgical ablation.

Radiation Exposure During Transcatheter Valve Replacement: What Cardiac Surgeons Need to Know

BACKGROUND

Transcatheter aortic valve replacement (TAVR) and transcatheter mitral valve replacement expose operators to radiation. These procedures differ primarily in whether they are performed via a transfemoral (TF) or an alternative access (AA) approach. This study compared operator radiation exposure during transcatheter valve implantation when performed via a TF vs an AA approach, when performed in a catheterization lab vs a hybrid operating room (OR), and investigated the potential benefit of disposable shielding.

METHODS

Dosimeters were worn during TAVR-TF (n = 50) and TAVR-AA (n = 31) procedures by operators. All TAVR-AA procedures were performed in a hybrid OR and TF procedures were performed in either catheterization labs (n = 16) or a hybrid OR (n = 34). Disposable radiation shielding pads (RADPAD; Worldwide Innovations and Technologies, Inc, Kansas City) or a placebo were added in a randomized, blinded fashion.

RESULTS

Team radiation exposure was higher after TAVR-AA vs TAVR-TF (median 15.1 mRad [interquartile range: IQR 8.6, 32.4] vs 5.5 mRad [IQR 2.4, 9.8], P < .001). TAVR-TF procedures required the same amount of fluoroscopy time regardless of where they were performed (20.3 ± 7.4 min in hybrid OR vs 19.0 ± 6.4 min in catheterization lab, P = .55). However, radiation exposure for TAVR-TF remained higher when performed in a hybrid OR (median 9.0 mRad [IQR 4.5, 11.9] vs 2.2 mRad [IQR 1.3, 2.8], P < .001). Radiation exposure was greatest for TAVR-AA (median 15.1 mRad [IQR 8.6, 32.4]). The use of RADPAD did not decrease radiation exposure (median 9.0 mRad [IQR 4.5, 14.7] vs 9.4 mRad [IQR 2.8, 19.5], P = .82).

CONCLUSIONS

Procedures performed in the hybrid OR were associated with higher operator radiation exposure. In comparison with the TF approach, AA cases had the highest levels of operator radiation. This is particularly important in cases of transcatheter mitral valve replacement that can only be done via an AA approach. The use of disposable radiation shielding in this series did not attenuate operator radiation exposure. Radiation shielding within hybrid ORs should be scrutinized in an effort to remain on par with that found within catheterization labs.

Long-Term Survival Prediction for Coronary Artery Bypass Grafting: Validation of the ASCERT Model Compared With The Society of Thoracic Surgeons Predicted Risk of Mortality

BACKGROUND

The recently developed American College of Cardiology Foundation-Society of Thoracic Surgeons (STS) Collaboration on the Comparative Effectiveness of Revascularization Strategy (ASCERT) Long-Term Survival Probability Calculator is a valuable addition to existing short-term risk-prediction tools for cardiac surgical procedures but has yet to be externally validated.

METHODS

Institutional data of 654 patients aged 65 years or older undergoing isolated coronary artery bypass grafting between 2005 and 2010 were reviewed. Predicted survival probabilities were calculated using the ASCERT model. Survival data were collected using the Social Security Death Index and institutional medical records. Model calibration and discrimination were assessed for the overall sample and for risk-stratified subgroups based on (1) ASCERT 7-year survival probability and (2) the predicted risk of mortality (PROM) from the STS Short-Term Risk Calculator. Logistic regression analysis was performed to evaluate additional perioperative variables contributing to death.

RESULTS

Overall survival was 92.1% (569 of 597) at 1 year and 50.5% (164 of 325) at 7 years. Calibration assessment found no significant differences between predicted and actual survival curves for the overall sample or for the risk-stratified subgroups, whether stratified by predicted 7-year survival or by PROM. Discriminative performance was comparable between the ASCERT and PROM models for 7-year survival prediction (p < 0.001 for both; C-statistic = 0.815 for ASCERT and 0.781 for PROM). Prolonged ventilation, stroke, and hospital length of stay were also predictive of long-term death.

CONCLUSIONS

The ASCERT survival probability calculator was externally validated for prediction of long-term survival after coronary artery bypass grafting in all risk groups. The widely used STS PROM performed comparably as a predictor of long-term survival. Both tools provide important information for preoperative decision making and patient counseling about potential outcomes after coronary artery bypass grafting.

Performance of the Cox-maze IV procedure is associated with improved long-term survival in patients with atrial fibrillation undergoing cardiac surgery

OBJECTIVE

Atrial fibrillation (AF) is associated with an increased mortality risk. The Cox-maze IV procedure (CM4) performed concomitantly with other cardiac procedures has been shown to be effective for restoring sinus rhythm. However, few data have been published on the late survival of patients undergoing a concomitant CM4.

METHODS

Patients undergoing cardiac surgery were retrospectively reviewed from 2001 to 2016 (n = 10,859). Patients were stratified into 3 groups: patients with a history of AF receiving a concomitant CM4 (CM4; n = 438), patients with a history of AF unaddressed during surgery (Untreated AF; n = 1510), and patients without AF history (No AF; n = 8911). Propensity score matching was conducted between the CM4 and Untreated AF groups, and between the CM4 and No AF groups.

RESULTS

Thirty-day mortality was similar between the matched groups. Kaplan-Meier analysis showed greater survival for CM4 compared to Untreated AF (P = .004). Ten-year survival was 62% for CM4 and 42% for Untreated AF. Adjusted hazard ratio was 0.47 (95% confidence interval, 0.26-0.86, P = .014). No difference in survival was found between CM4 and No AF groups with the Kaplan-Meier analysis (P = .847). Ten-year survival was 63% for CM4 and 55% for No AF. Adjusted hazard ratio was 1.03 (95% confidence interval, 0.51-2.11, P = .929).

CONCLUSIONS

For selected patients with a history of AF undergoing cardiac surgery, concomitant CM4 did not add significantly to postoperative morbidity or mortality and was associated with improved late survival compared with patients with untreated AF and a similar survival to patients without a history of AF.

Blood Pressure and Arterial Load After Transcatheter Aortic Valve Replacement for Aortic Stenosis

Background—

After aortic valve replacement, left ventricular afterload is often characterized by the residual valve obstruction. Our objective was to determine whether higher systemic arterial afterload—as reflected in blood pressure, pulsatile and resistive load—is associated with adverse clinical outcomes after transcatheter aortic valve replacement (TAVR).

Methods and Results—

Total, pulsatile, and resistive arterial load were measured in 2141 patients with severe aortic stenosis treated with TAVR in the PARTNER I trial (Placement of Aortic Transcatheter Valve) who had systolic blood pressure (SBP) and an echocardiogram obtained 30 days after TAVR. The primary end point was 30-day to 1-year all-cause mortality. Lower SBP at 30 days after TAVR was associated with higher mortality (20.0% for SBP 100–129 mm Hg versus 12.0% for SBP 130–170 mm Hg; P <0.001). This association remained significant after adjustment, was consistent across subgroups, and confirmed in sensitivity analyses. In adjusted models that included SBP, higher total and pulsatile arterial load were associated with increased mortality ( P <0.001 for all), but resistive load was not. Patients with low 30-day SBP and high pulsatile load had a 3-fold higher mortality than those with high 30-day SBP and low pulsatile load (26.1% versus 8.1%; hazard ratio, 3.62; 95% confidence interval, 2.36–5.55).

Conclusions—

Even after relief of valve obstruction in patients with aortic stenosis, there is an independent association between post-TAVR blood pressure, systemic arterial load, and mortality. Blood pressure goals in patients with a history of aortic stenosis may need to be redefined. Increased pulsatile arterial load, rather than blood pressure, may be a target for adjunctive medical therapy to improve outcomes after TAVR.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00530894

Late results of the Cox-maze IV procedure in patients undergoing coronary artery bypass grafting

OBJECTIVE

Most patients with atrial fibrillation (AF) undergoing cardiac surgery do not receive concomitant ablation. This study reviewed outcomes of patients with AF undergoing Cox-maze IV (CMIV) procedure with radiofrequency and cryoablation and coronary artery bypass grafting (CABG) at our institution.

METHODS

Between the introduction of radiofrequency ablation in 2002 and 2015, 135 patients underwent left- or biatrial CMIV with CABG. Patients undergoing other cardiac procedures, except mitral valve repair, or who had emergent, reoperative, or off-pump procedures were excluded. Eighty-three patients remained in the study group after exclusion criteria were applied. Freedom from atrial tachyarrhythmias (ATAs) was ascertained using electrocardiogram, Holter monitor, or pacemaker interrogation at 1 to 5 years postoperatively.

RESULTS

Operative mortality was 3%. Freedom from ATAs at 1 year in the CMIV group was 98%, with 88% off antiarrhythmia drugs. Freedom from ATAs and antiarrhythmia drugs was 70% at 5 years.

CONCLUSIONS

The addition of CMIV to CABG resulted in excellent freedom from ATAs at 1 to 5 years. These patients are at increased risk for nonfatal complications compared with others undergoing concomitant surgical ablation.

Learning Alternative Access Approaches for Transcatheter Aortic Valve Replacement: Implications for New Transcatheter Aortic Valve Replacement Centers

BACKGROUND

Smaller transcatheter aortic valve replacement (TAVR) delivery systems have increased the number of patients eligible for transfemoral procedures while decreasing the need for transaortic (TAo) or transapical (TA) access. As a result, newer TAVR centers are likely to have less exposure to these alternative access techniques, making it harder to achieve proficiency. The purpose of this study was to evaluate the learning curve for TAVR approaches and compare perioperative outcomes.

METHODS

From January 2008 to December 2014, 400 patients underwent TAVR (transfemoral, n = 179; TA, n = 120; and TAo, n = 101)). Learning curves were constructed using metrics of contrast utilization, procedural, and fluoroscopy times. Outcomes during the learning curve were compared with after proficiency was achieved.

RESULTS

Depending on the metric, learning curves for all three routes differed slightly but all demonstrated proficiency by the 50th case. There were no significant differences in procedural times whereas improvements in contrast use were most notable for TA (69 ± 40 mL versus 50 ± 23 mL, p = 0.002). For both TA and TAo, fewer patients received transfusions once proficiency was reached (62% versus 34%, p = 0.003, and 42% versus 14%, p = 0.002, respectively). No differences in 30-day or 1-year mortality were seen before or after proficiency was reached for any approach.

CONCLUSIONS

The learning curves for TA and TAo are distinct but technical proficiency begins to develop by 25 cases and becomes complete by 50 cases for both approaches. Given the relatively low volume of alternative access, achieving technical proficiency may take significant time. However, technical proficiency had no effect on 30-day or 1-year mortality for any access approach.

Effect of tricuspid regurgitation and the right heart on survival after transcatheter aortic valve replacement: insights from the Placement of Aortic Transcatheter Valves II inoperable cohort

BACKGROUND

Tricuspid regurgitation (TR) and right ventricular (RV) dysfunction adversely affect outcomes in patients with heart failure or mitral valve disease, but their impact on outcomes in patients with aortic stenosis treated with transcatheter aortic valve replacement has not been well characterized.

METHODS AND RESULTS

Among 542 patients with symptomatic aortic stenosis treated in the Placement of Aortic Transcatheter Valves (PARTNER) II trial (inoperable cohort) with a Sapien or Sapien XT valve via a transfemoral approach, baseline TR severity, right atrial and RV size and RV function were evaluated by echocardiography according to established guidelines. One-year mortality was 16.9%, 17.2%, 32.6%, and 61.1% for patients with no/trace (n=167), mild (n=205), moderate (n=117), and severe (n=18) TR, respectively (P<0.001). Increasing severity of RV dysfunction as well as right atrial and RV enlargement were also associated with increased mortality (P<0.001). After multivariable adjustment, severe TR (hazard ratio, 3.20; 95% confidence interval, 1.50-6.82; P=0.003) and moderate TR (hazard ratio, 1.60; 95% confidence interval, 1.02-2.52; P=0.042) remained associated with increased mortality as did right atrial and RV enlargement, but not RV dysfunction. There was an interaction between TR and mitral regurgitation severity (P=0.04); the increased hazard of death associated with moderate/severe TR only occurred in those with no/trace/mild mitral regurgitation.

CONCLUSIONS

In inoperable patients treated with transcatheter aortic valve replacement, moderate or severe TR and right heart enlargement are independently associated with increased 1-year mortality; however, the association between moderate or severe TR and an increased hazard of death was only found in those with minimal mitral regurgitation at baseline. These findings may improve our assessment of anticipated benefit from transcatheter aortic valve replacement and support the need for future studies on TR and the right heart, including whether concomitant treatment of TR in operable but high-risk patients with aortic stenosis is warranted.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01314313.

Delirium after surgical and transcatheter aortic valve replacement is associated with increased mortality

OBJECTIVE

The purpose of this study was to determine the incidence and clinical significance of postoperative delirium (PD) in patients with aortic stenosis undergoing surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR).

METHOD

Between 2010 and 2013, 427 patients underwent TAVR (n = 168) or SAVR (n = 259) and were screened for PD using the Confusion Assessment Method for the Intensive Care Unit. The incidence of PD in both treatment groups was determined and its association with morbidity and mortality was retrospectively compared.

RESULTS

PD occurred in 135 patients (32%) with a similar incidence between SAVR (33% [86 out of 259]) and TAVR (29% [49 out of 168]) (P = .40). TAVR by transfemoral approach had the lowest incidence of PD compared with SAVR (18% vs 33%; P = .025) or TAVR when performed by alternative access techniques (18% vs 35%; P = .02). Delirium was associated with longer initial intensive care unit stay (70 vs 27 hours), intensive care unit readmission (10% [14 out of 135] vs 2% [6 out of 292]), and longer hospital stay (8 vs 6 days) (P < .001 for all). PD was associated with increased mortality at 30 days (7% vs 1%; P < .001) and 1 year (21% vs 8%; P < .001). After multivariable adjustment, PD remained associated with increased 1-year mortality (hazard ratio, 3.02; 95% confidence interval, 1.75-5.23; P < .001). There was no interaction between PD and aortic valve replacement approach with respect to 1-year mortality (P = .12). Among propensity-matched patients (n = 170), SAVR-treated patients had a higher incidence of PD than TAVR-treated patients (51% vs 29%; P = .004).

CONCLUSIONS

PD occurs commonly after SAVR and TAVR and is associated with increased morbidity and mortality. Given the high incidence of PD and its associated adverse outcomes, further studies are needed to minimize PD and potentially improve patient outcomes.

Preoperative pulmonary function tests predict mortality after surgical or transcatheter aortic valve replacement

OBJECTIVES

To determine the role of preoperative pulmonary function tests (PFTs) in patients with aortic stenosis (AS) evaluated for aortic valve replacement (AVR), and to evaluate the association between lung disease and mortality in specific subgroups.

METHODS

Between 2008 and 2013, 535 patients with preoperative PFTs underwent AVR (transcatheter AVR [TAVR], n = 246; surgical AVR [SAVR], n = 289). The severity of lung disease determined by the Society of Thoracic Surgeons (STS) definition was evaluated in those with and without a clinical suspicion for lung disease (smoking, inhaled steroids/bronchodilators, or home oxygen). The association between lung disease and 1-year mortality was evaluated.

RESULTS

Of the 186 patients (35%) without suspected lung disease, 39 (21%) had moderate/severe lung disease by PFT analysis. Among all patients, 1-year mortality was 12% in those with no lung disease, 17% in those with no mild lung disease, 22% in those with moderate lung disease, and 31% in those with severe lung disease (P < .001, log-rank test). After adjustment, moderate/severe lung disease was associated with increased 1-year mortality (adjusted hazard ratio, 2.07; 95% confidence interval, 1.30-3.29; P = .002); this association was not altered by smoking history, suspicion of lung disease, New York Heart Association class, or AVR type (interaction P value nonsignificant for all).

CONCLUSIONS

In patients with AS evaluated for AVR, the STS risk score is significantly influenced by the severity of lung disease, which is determined predominantly by PFT results. Even when lung disease is not suspected, PFTs are abnormal in many patients undergoing AVR. Moderate/severe lung disease, diagnosed predominantly by PFTs, is an independent predictor of mortality after SAVR or TAVR. Collectively, these findings suggest that PFTs should be a routine part of the risk stratification of patients considered for AVR.

Detection of Atrial Fibrillation After Surgical Ablation: Conventional Versus Continuous Monitoring

BACKGROUND

Current guidelines recommend at least 24-hour Holter monitoring at 6-month intervals to evaluate the recurrence of atrial fibrillation (AF) after surgical ablation. In this prospective multicenter study, conventional intermittent methods of AF monitoring were compared with continuous monitoring using an implantable loop recorder (ILR).

METHODS

From August 2011 to January 2014, 47 patients receiving surgical treatment for AF at 2 institutions had an ILR placed at the time of operation. Each atrial tachyarrhythmia (ATA) of 2 minutes or more was saved. Patients transmitted ILR recordings bimonthly or after any symptomatic event. Up to 27 minutes of data was stored before files were overwritten. Patients also underwent electrocardiography (ECG) and 24-hour Holter monitoring at 3, 6, and 12 months. ILR compliance was defined as any transmission between 0 and 3 months, 3 and 6 months, or 6 and 12 months. Freedom from ATAs was calculated and compared.

RESULTS

ILR compliance at 12 months was 93% compared with ECG and Holter monitoring compliance of 85% and 76%, respectively. ILR devices reported a total of 20,878 ATAs. Of these, 11% of episodes were available for review and 46% were confirmed as AF. Freedom from ATAs was no different between continuous and intermittent monitoring at 1 year. Symptomatic events accounted for 187 episodes; however, only 10% were confirmed as AF.

CONCLUSIONS

ILR was equivalent at detecting ATAs when compared with Holter monitoring or ECG. However, the high rate of false-positive readings and the limited number of events available for review present barriers to broad implementation of this form of monitoring. Very few symptomatic events were AF on review.

Clinical and Functional Outcomes Associated With Myocardial Injury After Transfemoral and Transapical Transcatheter Aortic Valve Replacement: A Subanalysis From the PARTNER Trial (Placement of Aortic Transcatheter Valves)

OBJECTIVES

This study sought to clarify the clinical and echocardiographic prognostic implication of myocardial injury after transcatheter aortic valve replacement (TAVR).

BACKGROUND

The clinical significance of cardiac biomarker elevation after TAVR remains unclear.

METHODS

Patients treated with TAVR in the PARTNER (Placement of Aortic Transcatheter Valves) trial were divided into tertiles (T1, T2, T3) based on the difference between the values on post-procedure day 1 and the baseline values of 2 cardiac biomarkers: cardiac troponin I (ΔcTnI); and creatine kinase-myocardial band (ΔCK-MB) fraction. Patients were stratified according to their access route: transfemoral (TF) (n = 1,840) or transapical (TA) (n = 1,173).

RESULTS

At 30 days after TF-TAVR, patients in the highest tertile (T3) of cardiac biomarker elevation had a higher rate of all-cause mortality (ΔcTnI: T3: 5.4% vs. T1: 0.5%, p = 0.006; ΔCK-MB: T3: 5.7% vs. T1: 0.9%, p = 0.006) and cardiovascular mortality (ΔcTnI: T3: 4.9% vs. T1: 0.5%, p = 0.01; ΔCK-MB: T3: 3.9% vs. T1: 0.5%, p = 0.02). At 1 year, only patients in the highest CK-MB tertile had higher rates of all-cause (25.4% vs. 16.8%, p = 0.02) and cardiovascular (10.3% vs. 5.0%) mortality. Multivariable analysis demonstrated that greater release of cardiac biomarkers was independently associated with increased mortality in the TF population. After TA-TAVR, being in the highest tertile of cardiac biomarker elevation had no influence on clinical and echocardiographic outcomes at 30 days and 1 year.

CONCLUSIONS

After TF-TAVR, a greater degree of myocardial injury was associated with higher rates of 30-day all-cause and cardiovascular mortality. At 1 year, being in the highest tertile of ΔCK-MB was correlated with a higher rate of all-cause and cardiac mortality. Finally, the level of myocardial injury after TA-TAVR had no impact on clinical and echocardiographic outcomes.

Risk stratification in patients with pulmonary hypertension undergoing transcatheter aortic valve replacement

OBJECTIVE

Pulmonary hypertension (PH) is associated with increased mortality after surgical or transcatheter aortic valve replacement (TAVR) for aortic stenosis (AS), and when the pulmonary artery pressure is particularly elevated, there may be questions about the clinical benefit of TAVR. We aimed to identify clinical and haemodynamic factors associated with increased mortality after TAVR among those with moderate/severe PH.

METHODS

Among patients with symptomatic AS at high or prohibitive surgical risk receiving TAVR in the Placement of Aortic Transcatheter Valves (PARTNER) I randomised trial or registry, 2180 patients with an invasive measurement of mean pulmonary artery pressure (mPAP) recorded were included, and moderate/severe PH was defined as an mPAP ≥35 mm Hg.

RESULTS

Increasing severity of PH was associated with progressively worse 1-year all-cause mortality: none (n=785, 18.6%), mild (n=838, 22.7%) and moderate/severe (n=557, 25.0%) (p=0.01). The increased hazard of mortality associated with moderate/severe PH was observed in females, but not males (interaction p=0.03). In adjusted analyses, females with moderate/severe PH had an increased hazard of death at 1 year compared with females without PH (adjusted HR 2.14, 95% CI 1.44 to 3.18), whereas those with mild PH did not. Among males, there was no increased hazard of death associated with any severity of PH. In a multivariable Cox model of patients with moderate/severe PH, oxygen-dependent lung disease, inability to perform a 6 min walk, impaired renal function and lower aortic valve mean gradient were independently associated with increased 1-year mortality (p<0.05 for all), whereas several haemodynamic indices were not. A risk score, including these factors, was able to identify patients with a 15% vs 59% 1-year mortality.

CONCLUSIONS

The relationship between moderate/severe PH and increased mortality after TAVR is altered by sex, and clinical factors appear to be more influential in stratifying risk than haemodynamic indices. These findings may have implications for the evaluation of and treatment decisions for patients referred for TAVR with significant PH.

TRIAL REGISTRATION

NCT00530894.

Late outcomes after the Cox maze IV procedure for atrial fibrillation

OBJECTIVE

The Cox maze IV procedure (CMPIV) has been established as the gold standard for surgical ablation; however, late outcomes using current consensus definitions of treatment failure have not been well described. To compare to reported outcomes of catheter-based ablation, we report our institutional outcomes of patients who underwent a left-sided or biatrial CMPIV at 5 years of follow-up.

METHODS

Between January 2002 and September 2014, data were collected prospectively on 576 patients with AF who underwent a CMPIV (n = 532) or left-sided CMPIV (n = 44). Perioperative variables and long-term freedom from AF, with and without AADs, were compared in multiple subgroups.

RESULTS

Follow-up at any time point was 89%. At 5 years, overall freedom from AF was 93 of 119 (78%), and freedom from AF off AADs was 77 of 177 (66%). No differences were found in freedom from AF, with or without AADs, at 1, 2, 3, 4, and 5 years for patients with paroxysmal AF (n = 204) versus with persistent/longstanding persistent AF (n = 305), or for those who underwent standalone versus a concomitant CMP. Duration of preoperative AF and hospital length of stay were the best predictors of failure at 5 years.

CONCLUSIONS

The outcomes of the CMPIV remain good at late follow-up. The type of preoperative AF or the addition of a concomitant procedure did not affect late success. The results of the CMPIV remain superior to those reported for catheter ablation and other forms of surgical AF ablation, especially for patients with persistent or longstanding AF.

Outcomes in Nonagenarians Undergoing Transcatheter Aortic Valve Replacement in the PARTNER-I Trial

BACKGROUND

This study describes short-term and mid-term outcomes of nonagenarian patients undergoing transfemoral or transapical transcatheter aortic valve replacement (TAVR) in the Placement of Aortic Transcatheter Valve (PARTNER)-I trial.

METHODS

From April 2007 to February 2012, 531 nonagenarians, mean age 93 ± 2.1 years, underwent TAVR with a balloon-expandable prosthesis in the PARTNER-I trial: 329 through transfemoral (TF-TAVR) and 202 transapical (TA-TAVR) access. Clinical events were adjudicated and echocardiographic results analyzed in a core laboratory. Quality of life (QoL) data were obtained up to 1 year post-TAVR. Time-varying all-cause mortality was referenced to that of an age-sex-race-matched US population.

RESULTS

For TF-TAVR, post-procedure 30-day stroke risk was 3.6%; major adverse events occurred in 35% of patients; 30-day paravalvular leak was greater than moderate in 1.4%; median post-procedure length of stay (LOS) was 5 days. Thirty-day mortality was 4.0% and 3-year mortality 48% (44% for the matched population). By 6 months, most QoL measures had stabilized at a level considerably better than baseline, with Kansas City Cardiomyopathy Questionnaire (KCCQ) 72 ± 21. For TA-TAVR, post-procedure 30-day stroke risk was 2.0%; major adverse events 32%; 30-day paravalvular leak was greater than moderate in 0.61%; and median post-procedure LOS was 8 days. Thirty-day mortality was 12% and 3-year mortality 54% (42% for the matched population); KCCQ was 73 ± 23.

CONCLUSIONS

A TAVR can be performed in nonagenarians with acceptable short- and mid-term outcomes. Although TF- and TA-TAVR outcomes are not directly comparable, TA-TAVR appears to carry a higher risk of early death without a difference in intermediate-term mortality. Age alone should not preclude referral for TAVR in nonagenarians.

Prognostic utility of novel biomarkers of cardiovascular stress in patients with aortic stenosis undergoing valve replacement

OBJECTIVE

In heart failure populations without aortic stenosis (AS), the prognostic utility of multiple biomarkers in addition to clinical factors has been demonstrated. We aimed to determine whether multiple biomarkers of cardiovascular stress are associated with mortality in patients with AS undergoing aortic valve replacement (AVR) independent of clinical factors.

METHODS

From a prospective registry of patients with AS, 345 participants who were referred for and treated with AVR (transcatheter (n=183) or surgical (n=162)) were included. Eight biomarkers were measured on blood samples obtained prior to AVR: growth differentiation factor 15 (GDF15), soluble ST2 (sST2), amino-terminal pro-B-type natriuretic peptide (NTproBNP), galectin-3, high-sensitivity cardiac troponin T, myeloperoxidase, high-sensitivity C reactive protein and monocyte chemotactic protein-1. Biomarkers were evaluated based on median value (high vs low) in a Cox proportional hazards model for all-cause mortality and a parsimonious group of biomarkers selected. Mean follow-up was 1.9±1.2 years; 91 patients died.

RESULTS

Three biomarkers (GDF15, sST2 and NTproBNP) were retained in the model. One-year mortality was 5%, 12%, 18% and 33% for patients with 0 (n=79), 1 (n=96), 2 (n=87) and 3 (n=83) biomarkers elevated, respectively (p<0.001). After adjustment for the Society of Thoracic Surgeons (STS) risk score, a greater number of elevated biomarkers was associated with increased mortality (referent: 0 elevated): 1 elevated (HR 1.47, 95% CI 0.60 to 3.63, p=0.40), 2 elevated (HR 2.89, 95% CI 1.24 to 6.74, p=0.014) and 3 elevated (HR 4.59, 95% CI 1.97 to 10.71, p<0.001). Among patients at intermediate or high surgical risk (STS score ≥4), 1-year and 2-year mortality rates were 34% and 43% for patients with three biomarkers elevated versus 4% and 4% for patients with 0 biomarkers elevated. When added to the STS score, the number of biomarkers elevated provided a category-free net reclassification improvement of 64% at 1 year (p<0.001). The association between a greater number of elevated biomarkers and increased mortality after valve replacement was similar in the transcatheter and surgical AVR populations.

CONCLUSIONS

These findings demonstrate the potential utility of multiple biomarkers to aid in risk stratification of patients with AS. Further studies are needed to evaluate their utility in clinical decision-making in specific AS populations.

Systemic inflammatory response syndrome after transcatheter or surgical aortic valve replacement

OBJECTIVE

An inflammatory response after cardiac surgery is associated with worse clinical outcomes, but recent trials to attenuate it have been neutral. We evaluated the association between systemic inflammatory response syndrome (SIRS) and mortality after transcatheter (TAVR) and surgical aortic valve replacement (SAVR) for aortic stenosis (AS) and evaluated whether diabetes influenced this relationship.

METHODS

Patients (n=747) with severe AS treated with TAVR (n=264) or SAVR (n=483) between January 2008 and December 2013 were included and 37% had diabetes mellitus. SIRS was defined by four criteria 12-48 h after aortic valve replacement (AVR): (1) white blood cell count <4 or >12; (2) heart rate >90; (3) temperature <36 or >38°C; or (4) respiratory rate >20. Severe SIRS was defined as meeting all four criteria. The primary endpoint was 6-month all-cause mortality (60 deaths occurred by 6 months). Inverse probability weighting (IPW) was performed on 44 baseline and procedural variables to minimise confounding.

RESULTS

Severe SIRS developed in 6% of TAVR patients and 11% of SAVR patients (p=0.02). Six-month mortality tended to be higher in those with severe SIRS (15.5%) versus those without (7.4%) (p=0.07). After adjustment, severe SIRS was associated with higher 6-month mortality (IPW adjusted HR 2.77, 95% CI 2.04 to 3.76, p<0.001). Moreover, severe SIRS was more strongly associated with increased mortality in diabetic (IPW adjusted HR 4.12, 95% CI 2.69 to 6.31, p<0.001) than non-diabetic patients (IPW adjusted HR 1.74, 95% CI 1.10 to 2.73, p=0.02) (interaction p=0.007). The adverse effect of severe SIRS on mortality was similar after TAVR and SAVR.

CONCLUSIONS

Severe SIRS was associated with a higher mortality after SAVR or TAVR. It occurred more commonly after SAVR and had a greater effect on mortality in diabetic patients. These findings may have implications for treatment decisions in patients with AS, may help explain differences in outcomes between different AVR approaches and identify diabetic patients as a high-risk subgroup to target in clinical trials with therapies to attenuate SIRS.

Left main disease progression following left branch vessel percutaneous intervention in patients who are referred for coronary artery bypass grafting

BACKGROUND AND AIM OF THE STUDY

We studied patients presenting for coronary artery bypass grafting (CABG) with significant left main coronary artery disease (LMD) despite previously documented minimal or no LMD at percutaneous coronary intervention (PCI) for left-sided branch coronary artery disease.

METHODS

Patients undergoing CABG for LMD with previous PCI were separated into fast or slow stenosis progression using percent change in LMD from first PCI to CABG divided by time (progression velocity). Outcomes and Kaplan-Meier survival were compared between the two groups.

RESULTS

Between September 1997 and June 2010, 4837 patients underwent CABG with 1235 of them having previous PCI of which 118 had LMD and previous left-sided branch PCI. Using median progression velocity fast and slow progression groups were identified (0.53 ± 0.18 and 4.5 ± 4.8%/month, p < 0.001). Mean follow-up was 4.9 ± 3.6 years and 6.9 ± 3.9 years, respectively. Fast progression patients were younger (p = 0.042), with higher baseline LMD at PCI (16.4% vs. 9% stenosis, p = 0.025), and a mean of 2.5 years to LMD compared to 10.6 years for the slow group (p < 0.001). There was no difference between the groups in number or type of PCI and number or type of vessel intervened. Kaplan-Meier survival was similar at one, three, and five years.

CONCLUSIONS

Fast LMD progression patients were younger and made up 4.7% (59/1235) of patients undergoing CABG with a history of PCI. Rapid progression was not related to number, type of PCI, or branch vessel intervened.

Early left ventricular regional contractile impairment in chronic mitral regurgitation occurs in a consistent, heterogeneous pattern

OBJECTIVES

The clinical guidelines for asymptomatic patients with chronic mitral regurgitation (MR) use the ejection fraction (EF) to trigger surgical referral. We hypothesized that the EF is not sensitive enough to detect the earliest contractile injury in chronic MR and that the injury associated with chronic MR is not global but heterogeneous, occurring regionally and predictably, before the onset of global left ventricular (LV) dysfunction.

METHODS

Fifteen patients with chronic MR and normal LVEF by echocardiography underwent cardiac magnetic resonance imaging with tissue tagging. Point-specific comparisons (at 15,300 LV grid points) of multiple strain parameters to a normal human strain database allowed normalization of patient-specific regional contractile function. Data were mapped over patient-specific 3-dimensional geometry and averaged across 6 LV regions.

RESULTS

Global LV longitudinal and circumferential myocardial strains were normal for all 15 patients with MR compared with normal controls (P>.05). Despite preserved global function, the anteroseptum and posteroseptum demonstrated significantly worse contractile function compared with other LV regions (P=.003 and P=.035, respectively). Hypercontractile regions (lateral walls) appeared to compensate (P=.002) for the reduced septal contractile function, masking injury detection by global indexes.

CONCLUSIONS

The earliest contractile injury seen in patients with MR is heterogeneous and consistently distributed along the LV septum. Compensatory responses include hypercontractility of other regions. These data suggest that rather than relying on global LV contractile metrics, which cannot detect early injury, patients might be better served by undergoing directed surveillance of "sentinel" LV regions (LV septum) with high-resolution metrics of regional contractile function.

Prospective evaluation of patients readmitted after cardiac surgery: analysis of outcomes and identification of risk factors

OBJECTIVE

Reducing hospital readmissions after adult cardiac surgery is necessary as part of the solution to achieving improved efficiency in health care. Patients who had undergone cardiac surgery were studied to develop strategies that may diminish the need for hospital readmission.

METHODS

Over a 25-month period, 2096 patients underwent cardiac surgical procedures; 102 of these patients required readmission within 30 days of discharge. Time-matched patients (n = 249), not readmitted, served as a control group. Patient demographics and perioperative variables were analyzed by univariate analyses. Logistic regression analysis identified independent risk factors for readmission.

RESULTS

The most common diagnoses given for readmission were congestive heart failure (26 of 102, 25%), infection (23 of 102, 23%), and arrhythmias (15 of 102, 15%). The comorbidities more prevalent among readmitted patients were diminished ejection fraction (44% ± 17% vs 56% ± 13%; P < .0001), chronic obstructive pulmonary disease (23 of 102, 23% vs 23 of 249, 9%; P = .0008) and chronic renal insufficiency (26 of 102, 26% vs 24 of 249, 10%; P = .0001). Multivariate logistic regression identified chronic obstructive pulmonary disease (odds ratio [OR], 2.0; P = .05), diminished ejection fraction (OR, 0.8; P < .0001), a lower education level (OR, 0.5; P = .0001), and a prolonged length of stay (OR, 1.6; P = .009) as predictive of readmission. Failure to see a physician early in the postoperative period was associated with a 6-fold increase in the risk of readmission (P < .0001).

CONCLUSIONS

Patients readmitted after cardiac surgery have specific comorbidities and are of lower socioeconomic status. They are admitted most commonly for exacerbation of congestive heart failure or infectious reasons. This study suggests that seeing a physician early after discharge may have an impact on reducing readmissions after cardiac surgery.

Transcatheter versus surgical aortic valve replacement in patients with diabetes and severe aortic stenosis at high risk for surgery: an analysis of the PARTNER Trial (Placement of Aortic Transcatheter Valve)

OBJECTIVES

The goal of this study was to determine whether a less-invasive approach to aortic valve replacement (AVR) improves clinical outcomes in diabetic patients with aortic stenosis (AS).

BACKGROUND

Diabetes is associated with increased morbidity and mortality after surgical AVR for AS.

METHODS

Among treated patients with severe symptomatic AS at high risk for surgery in the PARTNER (Placement of Aortic Transcatheter Valve) trial, we examined outcomes stratified according to diabetes status of patients randomly assigned to receive transcatheter or surgical AVR. The primary outcome was all-cause mortality at 1 year.

RESULTS

Among 657 patients enrolled in PARTNER who underwent treatment, there were 275 patients with diabetes (145 transcatheter, 130 surgical). There was a significant interaction between diabetes and treatment group for 1-year all-cause mortality (p = 0.048). Among diabetic patients, all-cause mortality at 1 year was 18.0% in the transcatheter group and 27.4% in the surgical group (hazard ratio: 0.60 [95% confidence interval: 0.36 to 0.99]; p = 0.04). Results were consistent among patients treated via transfemoral or transapical routes. In contrast, among nondiabetic patients, there was no significant difference in all-cause mortality at 1 year (p = 0.48). Among diabetic patients, the 1-year rates of stroke were similar between treatment groups (3.5% transcatheter vs. 3.5% surgery; p = 0.88), but the rate of renal failure requiring dialysis >30 days was lower in the transcatheter group (0% vs. 6.1%; p = 0.003).

CONCLUSIONS

Among patients with diabetes and severe symptomatic AS at high risk for surgery, this post-hoc stratified analysis of the PARTNER trial suggests there is a survival benefit, no increase in stroke, and less renal failure from treatment with transcatheter AVR compared with surgical AVR. (The PARTNER Trial: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894).

Outcomes of transcatheter and surgical aortic valve replacement in high-risk patients with aortic stenosis and left ventricular dysfunction: results from the Placement of Aortic Transcatheter Valves (PARTNER) trial (cohort A)

BACKGROUND

The Placement of Aortic Transcatheter Valves (PARTNER) trial demonstrated similar survival after transcatheter and surgical aortic valve replacement (TAVR and SAVR, respectively) in high-risk patients with symptomatic, severe aortic stenosis. The aim of this study was to evaluate the effect of left ventricular (LV) dysfunction on clinical outcomes after TAVR and SAVR and the impact of aortic valve replacement technique on LV function.

METHODS AND RESULTS

The PARTNER trial randomized high-risk patients with severe aortic stenosis to TAVR or SAVR. Patients were stratified by the presence of LV ejection fraction (LVEF) <50%. All-cause mortality was similar for TAVR and SAVR at 30-days and 1 year regardless of baseline LV function and valve replacement technique. In patients with LV dysfunction, mean LVEF increased from 35.7±8.5% to 48.6±11.3% (P<0.0001) 1 year after TAVR and from 38.0±8.0% to 50.1±10.8% after SAVR (P<0.0001). Higher baseline LVEF (odds ratio, 0.90 [95% confidence interval, 0.86, 0.95]; P<0.0001) and previous permanent pacemaker (odds ratio, 0.34 [95% confidence interval, 0.15, 0.81]) were independently associated with reduced likelihood of ≥10% absolute LVEF improvement by 30 days; higher mean aortic valve gradient was associated with increased odds of LVEF improvement (odds ratio, 1.04 per 1 mm Hg [95% confidence interval, 1.01, 1.08]). Failure to improve LVEF by 30 days was associated with adverse 1-year outcomes after TAVR but not SAVR.

CONCLUSIONS

In high-risk patients with severe aortic stenosis and LV dysfunction, mortality rates and LV functional recovery were comparable between valve replacement techniques. TAVR is a feasible alternative for patients with symptomatic severe aortic stenosis and LV dysfunction who are at high risk for SAVR.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00530894.

The impact of previous catheter-based ablation on the efficacy of the Cox-maze IV procedure

BACKGROUND

Failed catheter-based ablation for the treatment of atrial fibrillation is an indication for the Cox-maze procedure. Many patients are referred for the Cox-maze IV procedure with recurrent atrial fibrillation after a previous catheter-based ablation, but the efficacy and safety of surgical management in these patients remains unclear.

METHODS

Data were collected prospectively on 129 consecutive patients who underwent a stand-alone Cox-maze IV procedure. Patients were grouped by the presence (n=61; 47%) or absence (n=68; 53%) of previous catheter ablation history. Follow-up was conducted at 3, 6, and 12 months (94% complete, mean 15.1±15.6 months) with electrocardiograms and 24-hour Holter monitoring.

RESULTS

In patients with no ablation history compared with those with, freedom from atrial tachyarrhythmias and antiarrhythmic drugs were similar at 3 months (73% versus 67%), 6 months (85% versus 83%), and 12 months (81% versus 87%; p<0.05 for all). Those who had failed previous catheter ablation had significantly smaller left atria and longer durations of atrial fibrillation, and were more likely to have persistent atrial fibrillation compared with the group without prior ablation history. All analyzed baseline patient characteristics and comorbidities were similar between the groups. No differences were found in complication rates or surrogate measures of operative difficulty.

CONCLUSIONS

The Cox-maze IV procedure is safe and effective in treating recurrent atrial fibrillation regardless of previous catheter ablation history. Surgical management should be considered in patients who have failed catheter ablation for the treatment of their atrial fibrillation.

The impact of CHADS2 score on late stroke after the Cox maze procedure

OBJECTIVE

The Heart Rhythm Society, European Heart Rhythm Association, and European Cardiac Arrhythmia Society jointly recommend indefinite warfarin anticoagulation in patients with CHADS2 (congestive heart failure, hypertension, age, diabetes, and stroke) score of at least 2 who have undergone ablation for atrial fibrillation. This study determined the impact of CHADS2 score on risk of late stroke or transient ischemic attack after the performance of a surgical Cox maze procedure.

METHODS

A retrospective review of 433 patients who underwent a Cox maze procedure at our institution was conducted. Three months after surgery, warfarin was discontinued regardless of CHADS2 score if the patient showed no evidence of atrial fibrillation, was off antiarrhythmic medications, and had no other indication for anticoagulation. A follow-up questionnaire was used to determine whether any neurologic event had occurred since surgery.

RESULTS

Follow-up was obtained for 90% of the study group (389/433) at a mean of 6.6 ± 5.0 years. Among these patients, 32% (125/389) had a CHADS2 score of at least 2, of whom only 40% (51/125) remained on long-term warfarin after surgery. Six patients had late neurologic events (annualized risk of 0.2%). Neither CHADS2 score nor warfarin anticoagulation was significantly associated with the occurrence of late neurologic events. Among the individual CHADS2 criteria, both diabetes mellitus and previous stroke or transient ischemic attack were predictive of late neurologic events.

CONCLUSIONS

The risk of stroke or transient ischemic attack in patients after a surgical Cox maze procedure was low and not associated with CHADS2 score or warfarin use. Given the known risks of warfarin, we recommend discontinuation of anticoagulation 3 months after the procedure if the patient has no evidence of atrial fibrillation, has discontinued antiarrhythmic medications, and is without any other indication for systemic anticoagulation.

Transcatheter aortic valve replacement

Aortic stenosis is the most common form of valvular heart disease in the Western world and until recently, surgical aortic valve replacement has been the only treatment available for patients with this disease that has been shown to improve both symptoms and survival. Transcatheter aortic valve replacement has emerged as a new therapy for patients with severe aortic stenosis who are poor surgical candidates due to their elevated surgical risk. As longer follow up is obtained and improvements continue to be made in the current available prostheses, transcatheter aortic valve replacement will likely become a treatment alternative for high-risk patients with severe aortic stenosis.

Surgical experience with cardiac papillary fibroelastoma over a 15-year period

BACKGROUND

Papillary fibroelastomas are rare, benign cardiac tumors. They are predominantly asymptomatic. However, they can lead to serious complications, namely thromboembolic events. Symptomatic lesions can be managed primarily with surgical excision and valvular preservation. Controversy exists as to the management of asymptomatic lesions.

METHODS

All patients diagnosed with cardiac papillary fibroelastoma between 1996 and 2012 at a single institution were queried for clinical and pathologic characteristics.

RESULTS

Twenty-three patients with 29 lesions were identified. Most lesions were solitary, less than 1.0 cm in diameter, and occurred in patients greater than 60 years of age. The most common presentation was thromboembolic complication. All were managed successfully with surgical excision. One patient developed a recurrence or metachronous lesion within 3 months of initial surgical intervention.

CONCLUSIONS

Papillary fibroelastomas are rare, benign, predominantly asymptomatic cardiac tumors that can cause potentially serious complications. The natural history and etiology of papillary fibroelastomas are largely unknown. Controversy exists over the management of asymptomatic lesions. However, there is consensus that symptomatic lesions should undergo surgical excision with valvular preservation when possible. A unique case of a possible papillary fibroelastoma recurrence is also described.

Cox-Maze IV results for patients with lone atrial fibrillation versus concomitant mitral disease

BACKGROUND

This study compared Cox-Maze IV (CMIV) outcomes for the treatment of atrial fibrillation (AF) in patients with lone AF vs those with AF and mitral valve (MV) disease.

METHODS

Since 2002, 200 patients have undergone a CMIV procedure for lone AF (n=101) or concomitantly with MV operations (n=99). Preoperative, perioperative, and late outcomes between these groups were compared. Data were collected prospectively and reported at 3, 6, and 12 months.

RESULTS

Lone AF patients had AF of longer duration; patients with AF and MV disease were older, with larger left atria and worse New York Heart Association classification (p<0.05). Operative mortality (1% vs 4%, p>0.05, respectively) was similar between both groups. Perioperative atrial tachyarrhythmias were more prevalent in patients with concomitant MV operations (57% vs 41%, p=0.03); however, freedom from AF and antiarrhythmics was similar for both groups at 12 months (76% and 77%). The only predictor for atrial tachyarrhythmia recurrence or arrhythmic drug dependence was failure to isolate the posterior left atrium (p<0.01).

CONCLUSIONS

Patients with AF and MV disease have distinct comorbidities compared with patients with lone AF. However, the CMIV is safe and effective in both groups and should be considered for patients with AF undergoing MV operations. Patients with MV disease had more atrial tachyarrhythmias at 3 months, but freedom from AF and antiarrhythmics was similar to patients with lone AF at 1 year. The posterior left atrium should be isolated in every patient, because this was the only predictor for failure of the CMIV for either group.

The cox-maze procedure for lone atrial fibrillation: a single-center experience over 2 decades

BACKGROUND

The Cox-Maze procedure (CMP) has achieved high success rates in the therapy of atrial fibrillation (AF) while becoming progressively less invasive. This report evaluates our experience with the CMP in the treatment of lone AF over 2 decades and compares the original cut-and-sew CMP-III to the ablation-assisted CMP-IV, which uses bipolar radiofrequency and cryoenergy to create the original lesion pattern.

METHODS AND RESULTS

Data were collected prospectively on 212 consecutive patients (mean age, 53.5±10.4 years; 78% male) who underwent a stand-alone CMP from 1992 through 2010. The median duration of preoperative AF was 6 (interquartile range, 2.9-11.5) years, with 48% paroxysmal and 52% persistent or long-standing persistent AF. Univariate analysis with preoperative and perioperative variables used as covariates for the CMP-III (n=112) and the CMP-IV (n=100) was performed. Overall, 30-day mortality was 1.4%, with no intraoperative deaths. Freedom from AF was 93%, and freedom from AF off antiarrhythmics was 82%, at a mean follow-up time of 3.6±3.1 years. Freedom from symptomatic AF at 10 years was 85%. Only 1 late stroke occurred, with 80% of patients not receiving anticoagulation therapy. The less invasive CMP-IV had significantly shorter cross-clamp times (41±13 versus 92±26 minutes; P<0.001) while achieving high success rates, with 90% freedom from AF and 84% freedom from AF off antiarrhythmics at 2 years.

CONCLUSIONS

The CMP, although simplified and shortened by alternative energy sources, has excellent results, even with improved follow-up and stricter definition of failure.

Differential modulation of right ventricular strain and right atrial mechanics in mild vs. severe pressure overload

Increased right atrial (RA) and ventricular (RV) chamber volumes are a late maladaptive response to chronic pulmonary hypertension. The purpose of the current investigation was to characterize the early compensatory changes that occur in the right heart during chronic RV pressure overload before the development of chamber dilation. Magnetic resonance imaging with radiofrequency tissue tagging was performed on dogs at baseline and after 10 wk of pulmonary artery banding to yield either mild RV pressure overload (36% rise in RV pressure; n = 5) or severe overload (250% rise in RV pressure; n = 4). The RV free wall was divided into three segments within a midventricular plane, and circumferential myocardial strain was calculated for each segment, the septum, and the left ventricle. Chamber volumes were calculated from stacked MRI images, and RA mechanics were characterized by calculating the RA reservoir, conduit, and pump contribution to RV filling. With mild RV overload, there were no changes in RV strain or RA function. With severe RV overload, RV circumferential strain diminished by 62% anterior (P = 0.04), 42% inferior (P = 0.03), and 50% in the septum (P = 0.02), with no change in the left ventricle (P = 0.12). RV filling became more dependent on RA conduit function, which increased from 30 ± 9 to 43 ± 13% (P = 0.01), than on RA reservoir function, which decreased from 47 ± 6 to 33 ± 4% (P = 0.04), with no change in RA pump function (P = 0.94). RA and RV volumes and RV ejection fraction were unchanged from baseline during either mild (P > 0.10) or severe RV pressure overload (P > 0.53). In response to severe RV pressure overload, RV myocardial strain is segmentally diminished and RV filling becomes more dependent on RA conduit rather than reservoir function. These compensatory mechanisms of the right heart occur early in chronic RV pressure overload before chamber dilation develops.

The Cox-maze IV procedure for lone atrial fibrillation: a single center experience in 100 consecutive patients

PURPOSE

The Cox-maze III procedure (CMP) has achieved high success rates for the surgical treatment of atrial fibrillation (AF). In 2002, our group introduced a simplified CMP, in which most incisions were replaced with linear lines of ablation using bipolar radiofrequency and cryoenergy. This operation, termed the CMP-IV, has significantly shortened operative times and allowed for a minimally invasive approach. This report evaluates our results in 100 consecutive patients undergoing a stand-alone CMP-IV.

METHODS

Data were collected prospectively on 100 patients (mean age, 56 ± 10 years) who underwent a CMP-IV from January 2002 through May 2010. All patients were available for follow-up with a mean follow-up of 17 ± 10 months. Electrocardiograms or 24-h Holter monitorings were obtained at 6, 12, and 24 months. Data were analyzed using a longitudinal database containing over 380 variables.

RESULTS

Thirty-one percent of patients had paroxysmal AF, with the remainder having persistent (6%) or longstanding persistent AF (63%). The mean preoperative duration of AF was 7.4 ± 6.7 years. The mean left atrial diameter was 4.7 ± 1.1 cm. In this group, 40 patients had failed with a mean of 2.6 ± 1.3 catheter ablations. Mean aortic cross-clamp time was 41 ± 13 min. There was one postoperative mortality. Postoperative freedom from AF was 93%, 90%, and 90% at 6, 12, and 24 months, respectively. Freedom from AF off antiarrhythmic medication was 82%, 82%, and 84% at 6, 12, and 24 months, respectively.

CONCLUSION

The less invasive CMP-IV has a high single procedure success rate, even with improved follow-up and stricter definitions of failure.

The Cox maze IV procedure: predictors of late recurrence

OBJECTIVES

The Cox maze III procedure achieved high cure rates and became the surgical gold standard for the treatment of atrial fibrillation. Because of its invasiveness, a more simplified ablation-assisted procedure, the Cox maze IV procedure, has been performed at our institution since January 2002. The study examined multiple preoperative and perioperative variables to determine predictors of late recurrence.

METHODS

Data were collected prospectively on 282 patients who underwent the Cox maze IV procedure from January 2002 through December 2009. Forty-two percent of patients had paroxysmal and 58% had either persistent or long-standing persistent atrial fibrillation. All patients were available for follow-up. Follow-up included electrocardiograms in all patients. Since 2006, 24-hour Holter monitoring was obtained in 94% of patients at 3, 6, and 12 months. Data were analyzed by means of logistic regression analysis at 12 months, with 13 preoperative and perioperative variables used as covariates.

RESULTS

Sixty-six percent of patients had a concomitant procedure. After an ablation-assisted Cox maze procedure, the freedom from atrial fibrillation was 89%, 93%, and 89% at 3, 6, and 12 months, respectively. The freedom from both atrial fibrillation and antiarrhythmic drugs was 63%, 79%, and 78% at 3, 6, and 12 months, respectively. The risk factors for atrial fibrillation recurrence at 1 year were enlarged left atrial diameter (P = .027), failure to isolate the entire posterior left atrium (P = .022), and early atrial tachyarrhythmias (P = .010).

CONCLUSIONS

The Cox maze IV procedure has a high success rate at 1 year, even with improved follow-up and stricter definitions of failure. In patients with large left atria, there might be a need for more extensive size reduction or expanded lesion sets.