Late onset of atrial fibrillation in patients undergoing mitral valve repair for type II dysfunction

New-onset postoperative atrial fibrillation after mitral valve surgery: Determinants and the effect on survival

Objective

Mitral valve surgery (MVS) carries substantial risk of postoperative atrial fibrillation (PAF). Identifying patients who benefit from prophylactic left atrial appendage amputation (LAAA) or maze is ill-defined. To guide such interventions, we determined preoperative predictors of PAF and investigated 3-year survival of patients with PAF.

Methods

We performed a retrospective analysis of patients undergoing isolated MVS (N = 670) between 2011 and 2021. Patients with preoperative atrial fibrillation, LAAA or pulmonary vein isolation were excluded. Patient characteristics were compared between those without PAF and those who developed transient or prolonged PAF. Predictors of any PAF and prolonged PAF were identified using multivariable regression analysis.

Results

In total, 504 patients without preoperative atrial fibrillation underwent isolated MVS. Of them, 303 patients (60.2%) developed PAF; 138 (27.3%) developed transient and 165 (32.7%) developed prolonged (beyond 30 days) PAF. Patients with PAF were older (65.7 vs 54.3 years, P < .001), with larger left atria (4.8 vs 4.3 cm, P < .001), greater prevalence of hypertension (60% vs 47.8%, P < .05), and were New York Heart Association class III/IV (36% vs 8.5%, P < .001). Independent predictors of PAF included left atria volume index (odds ratio [OR], 1.02; P < .003), older age (OR, 1.04; P < .001), heart failure (OR, 6.73; P < .001), and sternotomy (OR, 2.19; P < .002). Age, heart failure, and sternotomy were independent predictors of prolonged PAF. Patients with PAF had greater mortality at 3 years compared with those without PAF (5.3% vs 0.5%, P < .005). On multivariable analysis, PAF was associated with increased mortality (hazard ratio, 7.81; P < .046).

Conclusions

PAF is common after MVS and associated with late mortality. Older age, advanced heart failure, and sternotomy are associated with prolonged PAF. These factors may identify patients who would benefit from prophylactic LAAA or ablation during MVS.

Flow adjusted transmitral pressure gradient as a modified indicator of functional mitral stenosis after repair for degenerative mitral regurgitation

Background and Aim

After repair of degenerative mitral regurgitation (DMR), the focus is on functional mitral stenosis (FMS) when there is a decline of mitral hemodynamics. Yet, the clinical impacts and a standardized definition are still undecided. Since common mitral hemodynamic parameters are influenced by transmitral flow, the aim of this study is to seek the impact of flow adjusted transmitral pressure gradient (TMPG) by left ventricular stroke volume (LVSV) on the midterm outcomes.

Methods

Three hundred one patients who had undergone isolated mitral valve repair for degenerative lesions with annuloplasty prosthesis between October 2012 and June 2019 were included. Postoperative adverse events occurred in 20 patients (6.6%). Flow adjusted TMPG was defined as TMPG/LVSV.

Results

Common mitral hemodynamic parameters were not associated with adverse events. By multivariable analysis, patients’ age, left ventricular ejection fraction (LVEF) and mean TMPG/LVSV were isolated as independent predictors (adjusted hazard ratio: 1.05, 0.95, and 1.16; p = .037, .005, and .035). Flow adjusted TMPG was significantly higher in the full ring group compared to the partial band group (0.051 mmHg/ml, [0.038–0.068] vs. 0.041 mmHg/ml, [0.031–0.056]; p < .001) and had a significantly negative correlation with the size of the annuloplasty prosthesis (r = −0.37, p < .001).

Conclusions

Conventional mitral hemodynamic parameters were not associated with adverse cardiac events after repair for DMR. Adjustment by flow has a potential to advance pressure gradient to a more sensitive indicator of FMS associated with clinical outcomes.

Remote Heart Rhythm Monitoring by Photoplethysmography-Based Smartphone Technology After Cardiac Surgery: Prospective Observational Study

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia after cardiac surgery, yet the precise incidence and significance of arrhythmias after discharge home need to be better defined. Photoplethysmography (PPG)-based smartphone apps are promising tools to enable early detection and follow-up of arrhythmias.

OBJECTIVE

By using a PPG-based smartphone app, we aimed to gain more insight into the prevalence of AF and other rhythm-related complications upon discharge home after cardiac surgery and evaluate the implementation of this app into routine clinical care.

METHODS

In this prospective, single-center trial, patients recovering from cardiac surgery were asked to register their heart rhythm 3 times daily using a Food and Drug Administration-approved PPG-based app, for either 30 or 60 days after discharge home. Patients with permanent AF or a permanent pacemaker were excluded.

RESULTS

We included 24 patients (mean age 60.2 years, SD 12 years; 15/23, 65% male) who underwent coronary artery bypass grafting and/or valve surgery. During hospitalization, 39% (9/23) experienced postoperative AF. After discharge, the PPG app reported AF or atrial flutter in 5 patients. While the app notified flutter in 1 patient, this was a false positive, as electrocardiogram revealed a 2nd-degree, 2:1 atrioventricular block necessitating a permanent pacemaker. AF was confirmed in 4 patients (4/23, 17%) and interestingly, was associated with an underlying postoperative complication in 2 participants (pneumonia n=1, pericardial tamponade n=1). A significant increase in the proportion of measurements indicating sinus rhythm was observed when comparing the first to the second month of follow-up (P<.001). In the second month of follow-up, compliance was significantly lower with 2.2 (SD 0.7) measurements per day versus 3.0 (SD 0.8) measurements per day in the first month (P=.002). The majority of participants (17/23, 74%), as well as the surveyed primary care physicians, experienced positive value by using the app as they felt more involved in the postoperative rehabilitation.

CONCLUSIONS

Implementation of smartphone-based PPG technology enables detection of AF and other rhythm-related complications after cardiac surgery. An association between AF detection and an underlying complication was found in 2 patients. Therefore, smartphone-based PPG technology may supplement rehabilitation after cardiac surgery by acting as a sentinel for underlying complications, rhythm-related or otherwise.

Adverse remodeling in atrial fibrillation following isolated aortic valve replacement surgery

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmia with adverse clinical outcomes. Aortic valve replacement (AVR) is one of the most frequently performed cardiac surgeries, although there is scarce evidence on arrhythmic outcomes. We aimed to evaluate AF during the first year post- isolated aortic valve replacement surgery and its clinical, analytical, and echocardiographic predictors.

METHODS

Severe aortic stenosis patients with no prior atrial fibrillation submitted to isolated aortic valve replacement surgery were included in our study, of which 316 remained in sinus rhythm and 24 developed AF. We performed logistic regression searching for AF predictors and a longitudinal comparison between pre and post-operative echocardiographic data.

RESULTS

Postoperative AF (POAF), diabetes, and follow-up indexed Left Atrium Diameter (iLAD) were significantly higher in the group of patients developing AF. POAF and iLAD were independent AF predictors at follow-up. No differences between groups were found regarding baseline and follow-up echocardiographic data except for indexed Left Ventricle End-diastolic Diameter (LVED), which failed to decrease after surgery in the AF group.

CONCLUSIONS

POAF and iLAD independently predicted AF at 1 year following isolated AVR surgery in aortic stenosis patients with no AF history. iLVED did not decrease significantly at follow-up in AF patients, possibly reflecting adverse ventricular remodeling.

Prognostic significance of moderate primary mitral regurgitation and concomitant paroxysmal atrial fibrillation

BACKGROUND

Severe primary mitral regurgitation [degenerative MR (DMR)] is associated with poor outcomes, including cardiac death and hospitalization due to worsening heart failure. However, little information is available regarding the characteristics of moderate DMR and their impacts on prognostic outcome. The aim of the present study was to investigate the prognosis and its determinants in patients with moderate DMR.

METHODS

We retroactively reviewed 13,700 consecutive patients who underwent transthoracic echocardiography and selected those with moderate DMR but without other underlying cardiac diseases. We assessed the characteristics and event-free rate of patients with moderate DMR compared with those of age- and gender-matched patients with mild or no MR.

RESULTS

The cohort included 182 (1%) patients with moderate DMR, and these were compared with 182 age- and gender-matched patients with mild or no MR. During the follow-up period of 1376 ± 652 days, 30 patients (8%) met the composite endpoint defined as cardiac death or hospitalization due to worsening heart failure. Kaplan-Meier analysis showed that patients with moderate DMR were significantly associated with a poor outcome compared to patients with mild or no MR (log-rank test p < 0.0001). Cox proportional hazard ratio revealed that moderate DMR and paroxysmal atrial fibrillation (PAF) were the independent predictors of the composite endpoint.

CONCLUSIONS

Patients with moderate DMR and concomitant PAF had a significantly worse outcome compared to those with mild or no MR. Active surveillance and some intervention for patients with PAF and moderate DMR may be required.

Benefit and Risk of Minimally Invasive Mitral Valve Repair for Type II Dysfunction - Propensity Score-Matched Comparison

BACKGROUND

Despite the cosmetic benefits of the minimally invasive approach for mitral disease, the clinical benefit and risk are not fully known. We investigated the benefit and risk of minimally invasive mitral valve (MV) repair for type II dysfunction using propensity score-matched analysis.

METHODS AND RESULTS

Since 2001, 602 patients have undergone MV repair for type II dysfunction (464 with conventional median sternotomy and 138 with the minimally invasive approach). One-to-one matched analysis using the estimated propensity score based on 23 factors resulted in 93 well-matched patient pairs. There was no in-hospital death in both groups. The operation time was significantly shorter (P=0.002), blood transfusion was less frequent (P=0.04), extubation at the day of surgery was more frequently performed (P=0.017), and the length of hospital stay was significantly shorter in the minimally invasive group than in the sternotomy group (P<0.0001). On postoperative (P=0.02) and 1-year echocardiography (P=0.04), ejection fraction was lower in the minimally invasive group than in the sternotomy group. There were no significant differences in postoperative cerebral infarction, aortic dissection, deep sternal infection, or mid-term outcome between the groups.

CONCLUSIONS

Standard sternotomy and the minimally invasive approach provide similar good quality of MV repair for type II dysfunction. The minimally invasive approach is more likely to contribute to fast-track perioperative treatment than the standard sternotomy approach.