Prognosis of patients with frequent premature ventricular complexes and nonsustained ventricular tachycardia after coronary artery bypass graft surgery

COVID-19 and arrhythmia: The factors associated and the role of myocardial electrical impulse propagation. An observational study based on cardiac telemetric monitoring

Background

The heart is commonly involved in COVID-19, and rhythm disorders have been largely reported.

Objective

To evaluate the association of some non-cardiac and cardiac comorbidities and QT dispersion with arrhythmias and their impact on outcomes in hospitalized patients with COVID-19.

Methods

Each patient underwent cardiac telemetry monitoring through the entire hospitalization period, laboratory analyses, 12-lead ECG, and lung imaging examination. Patients with arrhythmia were divided into three groups (bradyarrhythmias, tachyarrhythmias, and tachy- and bradyarrhythmias).

Results

Two-hundred patients completed the study (males, 123; mean age, 70.1 years); of these, 80 patients (40%) exhibited rhythm disorders on telemetry. Patients with arrhythmia were older (p < 0.0001), had a greater number of comorbidities (p < 0.0001), higher values of creatinine (p = 0.007), B-type natriuretic peptide (p < 0.0001), troponin (p < 0.0001), C-reactive protein (p = 0.01), ferritin (p = 0.001), D-dimer (p < 0.0001), procalcitonin (p = 0.0008), QT interval (p = 0.002), QTc interval (p = 0.04), and QTc dispersion (p = 0.01), and lower values of sodium (p = 0.03), magnesium (p = 0.04), glomerular filtration rate (p < 0.0001), and hemoglobin (p = 0.008) as compared to patients without arrhythmia. By comparing the three subgroups of patients, no significant differences were found. At multivariate analysis, age [odds ratio (OR) = 1.14 (95% CI: 1.07–1.22); p = 0.0004], coronary artery disease [OR = 12.7 (95% CI: 2.38–68.01); p = 0.005], and circulating troponin [OR = 1.05 (95% CI: 1.003–1.10); p = 0.04] represented risk factors independently associated with arrhythmia. All-cause in-hospital mortality was ∼40-fold higher among patients with arrhythmia [OR = 39.66 (95% CI: 5.20–302.51); p = 0.0004].

Conclusion

Arrhythmias are associated with aging, coronary artery disease, subtle myocardial injury, hyperinflammatory status, coagulative unbalance, and prolonged QTc dispersion in patients with COVID-19, and confer a worse in-hospital prognosis. Given its usefulness, routinary use of cardiac telemetry should be encouraged in COVID wards.

Cardiac arrhythmias in patients with COVID-19: Lessons from 2300 telemetric monitoring days on the intensive care unit

BACKGROUND

Patients with COVID-19 seem to be prone to the development of arrhythmias. The objective of this trial was to determine the characteristics, clinical significance and therapeutic consequences of these arrhythmias in COVID-19 patients requiring intensive care unit (ICU) treatment.

METHODS AND RESULTS

A total of 113 consecutive patients (mean age 64.1 ± 14.3 years, 30 (26.5%) female) with positive PCR testing for SARS-CoV2 as well as radiographically confirmed pulmonary involvement admitted to the ICU from March to May 2020 were included and observed for a cumulative time of 2321 days. Fifty episodes of sustained atrial tachycardias, five episodes of sustained ventricular arrhythmias and thirty bradycardic events were documented. Sustained new onset atrial arrhythmias were associated with hemodynamic deterioration in 13 cases (35.1%). Patients with new onset atrial arrhythmias were older, showed higher levels of Hs-Troponin and NT-proBNP, and a more severe course of disease. The 5 ventricular arrhythmias (two ventricular tachycardias, two episodes of ventricular fibrillation, and one torsade de pointes tachycardia) were observed in 4 patients. All episodes could be terminated by immediate defibrillation/cardioversion. Five bradycardic events were associated with hemodynamic deterioration. Precipitating factors could be identified in 19 of 30 episodes (63.3%), no patient required cardiac pacing. Baseline characteristics were not significantly different between patients with or without bradycardic events.

CONCLUSION

Relevant arrhythmias are common in severely ill ICU patients with COVID-19. They are associated with worse courses of disease and require specific treatment. This makes daily close monitoring of telemetric data mandatory in this patient group.

Modulating Perioperative Ventricular Excitability

Ventricular arrhythmias are associated with significant morbidity and mortality. In the perioperative period, more than 10% of patients undergoing a general anesthetic have an abnormal heart rhythm. Arrhythmia development is a dynamic interplay between an arrhythmogenic substrate, myocardial electrophysiologic properties, modifying factors, and triggering factors. Imbalances in the autonomic nervous system can lead to increased myocardial excitability, which is a major contributor to the pathophysiology of ventricular tachyarrhythmias. Myocardial excitability and ventricular arrhythmogenesis is modulated perioperatively through hemodynamic management, electrolyte balance, anesthetic agents, or regional anesthetic and surgical techniques.

Common Postcardiothoracic Surgery Arrhythmias

Cardiac arrhythmias are common after cardiac surgery and have profound sequelae. Bradycardias are typically transient and have reversible causes; however, persistent atrioventricular block is an indicator for permanent pacemaker implantation after valvular surgery. Transcatheter aortic valve surgery is associated with even higher rates of permanent pacemaker implantation. Atrial fibrillation, the most common postoperative arrhythmia, is associated with ischemic stroke, myocardial infarction, congestive heart failure, and short-term mortality. Ventricular arrhythmias have extremely high in-hospital mortality, as well as long-term mortality for those who survive the initial event. Implantable cardioverter-defibrillators have been shown to reduce long-term mortality for these patients.

Incidence, Risk Factors, and Outcome of Cardiac Arrhythmia Postcardiac Surgery in Children

Objective

To study the incidence of postoperative cardiac arrhythmias in children undergoing cardiac surgery and to evaluate the risk factors and outcome of these patients.

Materials and Methods

This retrospective observational study was conducted in the cardiac pediatric intensive care unit and included children <18 years of age. Children were monitored in the early postoperative period (72 h) for any sustained rhythm abnormality and were classified using standard definition. Details of treatment and their response were assessed. Risk factors for arrhythmias were evaluated using multivariate logistic regression analysis.

Results

Five hundred and thirty-six children were included and the prevalence of arrhythmia was 14.4% (n = 77). The most common arrhythmia was complete heart block (CHB) (n = 28; 5.2%), followed by junctional ectopic tachycardia (JET) (n = 25; 4.7%), junctional escape rhythm (n = 13; 2.4%), supraventricular tachycardia (SVT) (n = 8; 1.5%), and ventricular tachycardia (VT) (n = 3; 0.6%). Cardiac pacing was required in all CHB; 8 (28.6%) required a permanent pacemaker. Six (24%) patients with JET responded to conventional measures; 19 (76.0%) patients required amiodarone and 5 (20%) required cooling to 34°C or cardiac pacing. Temporary cardiac pacing was required in 9 (69.2%) cases of junctional escape rhythm. Seven (87.5%) events of SVT responded to adenosine and 1 (12.5%) required cardioversion. Two (66.7%) of VT responded to cardioversion while 1 (33.3%) was refractory. Five (6.5%) patients with arrhythmia died. In the multivariate logistic regression analysis, age <1 year, risk adjustment for congenital heart surgery category ≥3, and cross-clamp time >67 min were independent risk factors.

Conclusion

Early postoperative period following cardiac surgery is extremely vulnerable to cardiac arrhythmias. Although majority are self-limiting, some can be life-threatening.

Coronary sinus as a site for stable temporary atrial pacing to tide over premature ventricular complex-triggered recurrent ventricular fibrillation in a patient with severe left ventricular dysfunction after coronary bypass surgery

Use of atrial pacing has been known, yet underutilized tool for effective temporary pacing whenever needed early after cardiac surgery. The reasons may be frequent failures of epicardial wires (fixed over atria intra-operative) leading to loss of capture. Endocardial atrial pacing sites for temporary pacing are unstable and hence continuous pacing with acceptable thresholds is impossible. We describe a case of ischemic cardiomyopathy and severe left ventricle systolic dysfunction who required atrial pacing post coronary artery bypass grafting (CABG) surgery for around 48–72 hours starting 4th day post operation when he had multiple episodes of ventricular fibrillation (VF) needing many defibrillation shocks. VF episodes were triggered by premature ventricular complexes (PVC) falling on as R on T. Episodes were refractory to anti-arrhythmic drugs and general anesthesia. These PVC were successfully overdriven by atrial pacing by fluoroscopically placing pacing lead in coronary sinus. This led to complete suppression of PVC induced VF for next 48–72 hours while the antiarrhythmic drugs were continued. Subsequently the patient was discharged in stable state. Atrial pacing, though quite valuable during the post-operative period after cardiac surgery, is underutilized, especially when pacing through surgically placed epicardial wire fails. This report is helpful in drawing attention towards coronary sinus (CS) as an alternate site for achieving stable, temporary atrial pacing during the post-operative period. This site can also be utilized for short term dual chamber pacing if required in post-operative state using transvenous CS site for atrial pacing and intraoperatively placed epicardial wire for ventricular pacing.

Postoperative arrhythmias after cardiac surgery: incidence, risk factors, and therapeutic management

Arrhythmias are a known complication after cardiac surgery and represent a major cause of morbidity, increased length of hospital stay, and economic costs. However, little is known about incidence, risk factors, and treatment of early postoperative arrhythmias. Both tachyarrhythmias and bradyarrhythmias can present in the postoperative period. In this setting, atrial fibrillation is the most common heart rhythm disorder. Postoperative atrial fibrillation is often self-limiting, but it may require anticoagulation therapy and either a rate or rhythm control strategy. However, ventricular arrhythmias and conduction disturbances can also occur. Sustained ventricular arrhythmias in the recovery period after cardiac surgery may warrant acute treatment and long-term preventive strategy in the absence of reversible causes. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur with the need for permanent pacing. We provide a complete and updated review about mechanisms, risk factors, and treatment strategies for the main postoperative arrhythmias.

Ventricular tachyarrhythmia after coronary bypass surgery: incidence and outcome

BACKGROUND

Ventricular tachyarrhythmia after coronary artery bypass graft is common and the occurrence has been described, but the incidence and risk factors are not well defined.

AIM

To evaluate the incidence of arrhythmias and to detect high-risk populations.

METHODS

In this prospective study, 856 consecutive patients undergoing coronary artery bypass graft were monitored for new-onset ventricular tachyarrhythmias: non-sustained monomorphic ventricular tachyarrhythmia, sustained monomorphic ventricular tachyarrhythmia, sustained polymorphic ventricular tachyarrhythmia, and ventricular fibrillation. Detailed analyses of the clinical, demographic, echocardiographic, and surgical findings and arrhythmias occurrence was carried out during 6 months of follow-up.

RESULTS

The incidence of ventricular tachyarrhythmia was 26.6% (17.6% non-sustained monomorphic ventricular tachycardia, 5.5% sustained monomorphic ventricular tachycardia, 0.8% sustained polymorphic ventricular tachycardia, and 2.7% ventricular fibrillation). The strongest degrees of statistical significance were for low ejection fraction (p = 0.01) and ischemic heart disease (p = 0.02). The incidence of ventricular fibrillation (61%) was greatest in the first 48 h after surgery. Postoperative myocardial infarction (p = 0.03) and hemodynamic instability (p = 0.05) were also predictors of arrhythmia occurrence. Recurrence of arrhythmia was highest in the ventricular fibrillation group (52%). The correlations between tachyarrhythmia, age, sex, electrolyte disorders, body mass index, and systemic or pulmonary hypertension were not significant.

CONCLUSION

In view of the strong relationship between ventricular arrhythmias and low ejection fraction, ischemic heart disease, coronary artery disease severity, postoperative myocardial infection, and hemodynamic impairment, continuous monitoring is necessary, especially in the first 48 h after coronary artery bypass surgery.

Management of arrhythmias in the perioperative setting

Perioperative arrhythmias are a common complication of surgery, with incidence ranging from 4% to 20% for noncardiothoracic procedures, depending on the type of surgery performed. The immediate postoperative period is a dynamic time and is associated with many conditions conducive to the development of postoperative arrhythmias. The presence of postoperative atrial fibrillation is associated with increased morbidity, ICU stay, length of hospitalization, and hospital costs. The associated burdens are expected to rise in the future, given that the population undergoing cardiac surgery is getting older and sicker. Thousands of patients undergo major surgery each year and a major complication of these procedures is the occurrence of perioperative arrhythmia. It is imperative for clinicians to be up-to-date on current management of these arrhythmias.

Determining the need for coronary revascularization by an exercise test assessment computer program (ETAP)

The rate at which coronary artery revascularization procedures are performed remains inconsistent, and their risks may be greater and long-term benefits less than imagined by the general public and open to considerable inter-individual variation. However, these risks and benefits can be explicitly estimated for an individual patient from a brief medical history and the results of a standard exercise test by a computer program that uses conventional medical decision making techniques. The program first estimates the prior and post-exercise test probability of coronary artery disease and then employs a decision analysis model to define the risks and benefits associated with different treatment options. These results are provided in a printed report that can become part of the clinical record to be reviewed with the patient. In contrast with traditional clinical intuition, the program consistently and explicitly defines the risks and benefits of coronary artery disease treatments. The program forces physicians and their patients to appraise critically the information and beliefs upon which they base their clinical decisions.

Ischemic preconditioning suppresses ventricular tachyarrhythmias after myocardial revascularization

BACKGROUND

Ventricular fibrillation (VF) and tachycardia (VT) are the common and potential life-threatening complications after CABG. Ischemic preconditioning (IP) has been proved effective in reducing ischemia reperfusion arrhythmia in animals and humans. Whether IP is effective in suppressing postoperative VF/VT in patients with CABG has not been studied.

METHODS AND RESULTS

Eighty-six patients with CABG with stable and unstable 3-vessel disease were equally randomly assigned into an IP and a control group. The patients who received IP received 2 periods of 2-minute ischemia followed by 3-minute reperfusion. Twenty-four-hour electrocardiographic data were collected. IP resulted in fewer cases of VF after declamping (48.8% versus 79.1% in IP and control, P=0.004) and a shorter VF period (2.28+/-0.44 versus 4.41+/-0.51 minutes, P=0.002). The episodes of VT were significantly reduced in patients in the IP group during early reperfusion and 24 hours after reperfusion (0.65+/-0.16 versus 3.71+/-0.46, P=0.000 and 0.07+/-0.04 versus 2.12+/-1.41, P=0.002, respectively). De novo sustained VT occurred in 3 control patients as against none in the IP group after surgery. As a result, IP significantly curtailed the mechanical ventilation period and reduced the need for inotropes.

CONCLUSIONS

IP significantly reduced postoperative VF/VT in patients with CABG with 3-vessel disease. Suppression of VT during early reperfusion and 24 hours after reperfusion suggests early and delayed IP phenomena in patients undergoing CABG surgery.

Cardiac surgery: postoperative arrhythmias

Arrhythmias are common after surgery, particularly after cardiac surgery. Atrial fibrillation is the most common arrhythmia encountered postoperatively, although ventricular arrhythmias and conduction disturbances can also occur. Older age is the most consistent predictor of postoperative atrial arrhythmias. beta-adrenergic blockers, amiodarone, and sotalol are the most effective at preventing postoperative atrial fibrillation. Sustained ventricular arrhythmias in the recovery period after cardiac surgery warrant aggressive therapy, usually with an implantable cardioverter-defibrillator in the absence of reversible causes. Postoperative, nonsustained ventricular tachycardia in the setting of left ventricular dysfunction and ischemic coronary disease also usually warrants risk stratification and possible treatment, often with electrophysiologic testing and implantation of an implantable cardioverter-defibrillator, if sustained ventricular arrhythmias are induced. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur and indicate a need for permanent pacing.

Ventricular tachyarrhythmias following coronary surgery: predisposing factors

The perioperative factors potentially associated with post-coronary artery bypass grafting (CABG) ventricular tachyarrhythmias (VT) onset have not been deeply investigated. Monomorphic or polymorphic ventricular tachycardia and ventricular fibrillation represent the most dreadful arrhythmic events that can complicate the postoperative course of CABG. As a consequence, the aim of our paper was to identify which perioperative variables might predict post-CABG VT occurrence. One hundred and fifty-two consecutive patients who underwent CABG surgery at our Institution were included in the study. Post-CABG VT occurred in 13 out of 152 patients (8.5%, six cases of monomorphic ventricular tachycardia and seven cases of ventricular fibrillation). At univariate analysis, VT patients were significantly younger (54.8+/-6.6 vs. 60.1+/-8.8, P=0.038), exhibited a more severe coronary artery disease (CAD) (number of diseased vessels 2.92+/-0.3 vs. 2.45+/-0.7, P=0.023, and percentage of patients with three-vessel CAD 91.7% vs. 57.3%, P=0.043) and received a greater number of CABGs than those remaining in sinus rhythm (SR) (percentage of patients receiving three or more CABGs 76. 9% vs. 38.8%, P1000 76.9% vs. 38%, Pnormal range 72.7% vs. 30.7%, P=0.014), electrolyte derangement (84.6% vs. 45.6%, P=0.017) and a severe haemodynamic impairment (need for IABP 23% vs. 2.9%, P1000, postoperative electrolyte imbalance, the need for three or more CABGs and of IABP all were independent correlates for VT. In conclusion, post-CABG VT seem to be related to the preexistence of a severe underlying coronary artery disease along with perioperative triggering factors such as acute ischemia, electrolytic disorders and a sudden haemodynamic impairment.

Perioperative correlates of malignant ventricular tachyarrhythmias complicating coronary surgery

Sustained ventricular tachyarrhythmias (VT), such as monomorphic or polymorphic ventricular tachycardia, and ventricular fibrillation, represent the most serious arrhythmic events that can complicate the postoperative course of coronary artery bypass grafting (CABG). The perioperative factors potentially associated with post-CABG sustained VT onset have not been thoroughly investigated. As a consequence, the aim of our study was to identify which perioperative variables might predict post-CABG VT occurrence. One hundred and fifty-two consecutive patients who underwent CABG surgery at our Institute were included in the study. Post-CABG VT occurred in 13 out of 152 patients (8.5%, six cases of monomorphic ventricular tachycardia and seven cases of ventricular fibrillation). Univariate analysis revealed that VT patients were significantly younger (54.8 +/- 6.6 vs 60.1 +/- 8.8, P = 0.038), exhibited more severe coronary artery disease (CAD) (no. of diseased vessels, 2.92 +/- 0.3 vs 2.45 +/- 0.7, P = 0.023; and percentage of patients with three-vessel CAD, 91.7 vs 57.3%, P = 0.043), and received a greater number of CABGs than those remaining in sinus rhythm (SR) (percentage of patients receiving three or more CABGs, 76.9 vs 38.8%, P = 0.018) Moreover, VT patients more frequently developed intra- or postoperative myocardial infarction (total CK > 1,000, 76.9 vs 38%, P = 0.016; and MB-CK > normal range, 72.7 vs 30.7%, P = 0.014), electrolyte derangement (84.6 vs 45.6%, P = 0.017), and a severe hemodynamic impairment (need for intra-aortic balloon pump (IABP), 23 vs 2.9%, P = 0.009). On multivariate analysis, total CK > 1,000, postoperative electrolyte imbalance, the need for three or more CABGs, and for IABP all were independent correlates for VT. In conclusion, post-CABG VT seem to be related to the preexistence of a severe underlying coronary artery disease along with perioperative triggering factors, such as acute ischemia, electrolytic disorders, and sudden hemodynamic impairment.