Page 66 - Read Online

Page 12 of 21 Dokko et al. Vessel Plus 2022;6:37 https://dx.doi.org/10.20517/2574-1209.2021.121

randomized control trials for the use of these anti-inflammatory treatments following MV surgery
specifically is lacking.

Currently, studies on prophylactic surgical or transcatheter ablation in MV surgery are few to none due to
the uncertainty in benefits and risks of ablation in patients who present with sinus rhythm and the
frequently transient nature of POAF [127,128] . Prophylactic surgical ablation has been reported for “high risk”
[129]
(e.g., rheumatic heart disease patients undergoing MV repair) procedures . As these high-risk patient
populations are rarely found within the United States; however, this prophylactic approach to prevent atrial
fibrillation is not commonplace. A recent study with a mean follow-up of 23 months has shown
prophylactic maze surgical ablation to be effective in patients with congenital heart disease, resulting in
reduced burden or freedom from arrhythmias without early or late mortality but not without
[129]
recurrence . Further research on how to optimize the prevention of new-onset POAF in high-risk patients
undergoing specific surgery procedures (i.e., MV-related) is warranted. As of now, for patients with POAF
that persists after either MV surgery or concomitant surgical ablation, transcatheter ablation is an option,
and its outcomes are detailed in Section 2.4.2 [130,131] .

Outcomes
Surgical and transcatheter mitral valve procedures
There is not a clear consensus on the impact of POAF on short- and long-term outcomes following MV
procedures. One study with 361 MV surgery patients and median follow-up of 3.1 years demonstrated that
POAF was an independent predictor of all-cause late mortality, defined as death beyond 30 days, but was
not associated with increased early mortality. This group experienced significantly more in-hospital
[6]
cerebrovascular events, which may have contributed to increased late mortality in these patients . Another
[132]
study by Doshi et al. with 2580 transcatheter MV repair patients showed no significant differences in
adjusted MACCE rates and in-hospital mortality for patients with and without POAF. However, patients
with POAF had longer median lengths of stay and higher associated resource utilization costs, which they
state may have been due to atrial fibrillation, older age and increased comorbidities in patients with
POAF . Other studies have shown similar non-significant differences in mortality between patients with
[132]
and without POAF after MV surgery, but show an increasing trend toward mortality or stroke and
increased risk of recurrent myocardial infarction [5,7,111] . Table 3 lists several multivariate models for long-
term morbidity and mortality in which POAF was model-eligible. Although more studies are needed on
short-term outcomes, POAF generally appears to have a harmful impact on long-term MV outcomes.

Additionally, the burden of pre-operative atrial fibrillation may be important as a predictor of short- and
long-term outcomes in MV repair procedures. Persistent atrial fibrillation has been associated with higher
mortality and hospitalization due to heart failure at 30 days compared to paroxysmal atrial fibrillation, but
showed similar 1-year outcomes . In a cohort study with a mean follow-up of 9 years, the risk of mortality
[87]
was greatest in patients with persistent atrial fibrillation compared to that of patients with paroxysmal atrial
fibrillation and least in patients with sinus rhythm, regardless of age, sex and comorbidities . However, a
[2]
more recent study of the Nationwide Readmission Database compared paroxysmal atrial fibrillation to non-
paroxysmal atrial fibrillation and did not show any significant difference in death, stroke or 30-day
readmission after transcatheter MV repair .
[54]

Transcatheter ablation
Although the optimal timing of transcatheter ablation after MV surgeries or surgical ablation is not yet
clear, transcatheter ablation generally appears to be safe and effective after both procedures. Performed a
median of 224 days [73.0; 424.8] after the original procedure, transcatheter ablation in patients with atrial