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Obeid et al. Vessel Plus 2022;6:43 https://dx.doi.org/10.20517/2574-1209.2021.136 Page 3 of 14

RESULTS
Incidence of AF prior to LVAD
In the published literature, the incidence of AF prior to LVAD implantation ranged between 12.1% to
57.6%. Across these studies, the cumulative AF incidence rate was estimated at 36.2%. The reported
incidence of other preoperative cardiac arrythmias ranged from 1.2% to 72.0%, with the cumulative
incidence for preoperative cardiac arrythmias estimated at 16.5% [Table 1]. Not surprisingly, AF was the
most frequent preoperative arrythmia reported for LVAD patients.

Post-LVAD predisposing factors and incidence of postoperative AF
Across the reviewed literature, a wide variety of risk factors were associated with postoperative AF (POAF)
for patients following LVAD implantation. Several studies documented that chronic obstructive pulmonary
disease (COPD) was a multivariable predictor of LVAD patients’ POAF. Additional predictors included
[17]
increasing age and renal insufficiency (OR 1.5, CI: 1.0-2.2) . Notably, female gender was found to be
significantly associated with POAF (OR 4.0, CI: 1.6-10.2) . For recurrent AF post-LVAD implantation, the
[16]
[16]
most important significant multivariable predictors included pre-LVAD AF (OR 18.5, CI: 6.6-51.8) as
well as increasing age (OR 1.04, CI: 1.01-1.07) and first-degree heart block based on pre-LVAD
[17]
electrocardiogram readings (OR 2.4, CI: 1.1-5.4) .
The post-LVAD patients’ new-onset and overall POAF rates were reported to vary greatly, ranging from
2.1% to 27.7% and 11.7% to 57.9%, respectively [Table 1]. Moreover, Deshmukh et al. indicated an increased
proportion of patients with POAF greater than 30 days post-LVAD implant (7.8% vs. 20.6%) . This range
[17]
of incidence rates is similar to that of AF following other cardiac interventions, which range from 10%-40%.

Most common clinical outcomes following LVAD implantation in the literature reporting
preoperative AF or POAF
From the included articles, the most common clinical outcomes following LVAD implantation in studies
that reported preoperative/postoperative AF were compiled [Table 2]. The most frequently reported clinical
outcomes included mortality, stroke (either ischemic or hemorrhagic), and bleeding events.

Literature risk factors associated with adverse outcomes following LVAD implantation
The most common clinical risk factors associated with adverse outcomes (mortality, stroke, bleeding events,
and thromboembolic events) have been catalogued in Tables 3-6. Across the literature reviewed, AF was not
found to be a univariate, multivariable, or Cox proportional hazards model predictor of bleeding or stroke-
related events. However, AF was occasionally noted to be a predictor of mortality and thromboembolic
events.

Effect of pre-OP AF on LVAD outcomes
AF induces turbulent flow and, consequently, hypercoagulability in the atria that can lead to
thromboembolic (TE) events. When AF is coupled with mechanical circulatory support, the inherent risk of
device thrombosis increases. If thrombosis occurs, this may subsequently lead to imminent life-threatening
circulatory arrest. Thus, early studies raised concerns for worse adverse outcomes in AF patients
undergoing LVAD implantation.

For AF patients, increased rates of TE events have been reported, including device thrombosis , increased
[15]
recurrence of ventricular arrhythmias , as well as increased adverse events and mortality despite
[27]
anticoagulation . To date, these limited reports for a pre-op AF impact have been based upon retrospective
[14]
cohort studies. For preoperative AF, however, prospective LVAD investigations may reveal a lower impact
for pre-op AF patients.