Clinical hypnosis for reduction of atrial fibrillation after coronary artery bypass graft surgery

DISCUSSION

Adverse effects of PAF are well established

The onset of PAF following CABG is a common complication that has been linked to increases in morbidity and mortality, length of stay in the ICU and hospital, and total hospital charges. Villareal et al found that the odds ratio for early mortality (within 30 days) for patients who experienced PAF after CABG was 1.4 (95% confidence interval, 1.12 to 1.68; P = .002).¹² In addition, patients with PAF had significantly higher rates of postoperative infections, renal failure, shock, failure of multiple organ systems, and cardiac arrest compared with those who did not have PAF.¹² A literature analysis by Maisel et al found that PAF increases the likelihood that cardiac surgery patients will need to return to the operating room, be readmitted to the ICU, and require prolonged ventilation or reintubation.¹³ Nickerson et al showed that PAF following cardiac surgery corresponded with an increase in length of stay in both the ICU and hospital.¹⁴

Our study showed statistically significant increases in postoperative hospital charges, postoperative hospital stay, and ICU stay among patients who experi­enced PAF following CABG. These findings are consistent with the current literature. In a study of 720 subjects undergoing CABG, Hravnak et al reported a 1.4-day increase in length of hospital stay and a 0.3­day increase in length of ICU stay among patients who had PAF compared with those who did not.¹⁵ A significant increase in postoperative hospital charges was also observed.¹⁵ Similarly, in a multicenter study of 2,417 patients undergoing isolated CABG procedures, Mathew et al observed increases in ICU stay and hospital stay among those patients who experienced PAF.² These findings indicate that the onset of PAF after CABG is a serious complication and that further study is warranted.

Hypnosis to prevent PAF: Suggestive evidence and mechanisms

Clinical hypnosis has been shown to reduce stress and anxiety in surgical patients and can be highly individualized to address the patient’s needs during the stress­ful preoperative period. Saadat et al found that hypnosis administered directly before ambulatory surgery using Ericksonian techniques reduced patients’ levels of anxiety by 56% from baseline.¹¹ In a South African study specifically in men undergoing CABG, de Klerk et al found that preoperative hypnotherapy led to reductions in both anxiety and depression at discharge that were maintained through 6-week follow-up.¹⁰

These findings, taken together with research linking clinical hypnosis to changes in the autonomic nervous system⁹ and the belief that PAF may result from transient autonomic dysfunction, suggest that hypnosis may reduce the incidence of PAF.

In a study of R-R interval dynamics prior to PAF in patients who had undergone CABG, Hogue et al showed that patients who experienced PAF had higher heart rates directly before PAF onset.¹⁶ Higher heart rates are associated with increased activity of the sympathetic nervous system and/or decreased activity of the parasympathetic nervous system. This finding supports our hypothesis of a relationship between PAF following CABG and excessive adrenergic activation. Chen et al have noted that catecholamine-mediated AF usually occurs in the presence of heart disease and that these types of attacks often happen during the day­time in association with physical or emotional stress.⁴

Bettoni and Zimmermann found that the onset of AF is preceded by a primary increase in adrenergic drive, which changes to increased vagal activity immediately before the occurrence.³ Tomita et al reported that sympathetic tone increases immediately before an occurrence of daytime AF.⁷ These results were supported by Lombardi et al, who detected signs of predominant sympathetic modulation and reduced vagal modulation of sinus node in AF episodes that started during the daytime.⁶ These episodes were characterized by atrial ectopic beats prior to onset.⁶

Modulations in baroreceptor reflex activity may provide further evidence of the importance of the sympathetic/parasympathetic balance in the initiation of AF. Suboptimal functioning of the baroreceptor reflex has been associated with arrhythmias and adverse cardiac events in patients and animal models. Loss of the protective effects of vagal activation has been postulated to increase vulnerability to sympathetically driven ischemia and malignant arrhythmias.¹⁷

Multiple studies have shown that the only conclusive predictor of PAF is age. Notably, heart rate variability is reduced with increased age.¹⁸ By measuring heart rate variability, Taggart et al showed that autonomic balance was improved in patients under induced stress when they were in a hypnotic state.¹⁹ Although no attempts were made to determine heart rate variability in our patient set, other studies have demonstrated an increase in heart rate variability during hypnosis. The results of our study suggest that clinical hypnosis using a personalized Ericksonian approach may have a beneficial effect on the incidence of PAF.

CONCLUSIONS

Clinical hypnosis appears to lower the incidence of PAF in patients undergoing CABG as well as to yield favorable trends toward reduced ICU and postoperative hospital stays, reduced hospital charges, and reduced use of narcotics. Although our study had a small sample size and lacked randomization, its positive results and the absence of side effects suggest that prospective randomized trials should be conducted to further delineate the role of hypnosis in the prevention of PAF. A better understanding of AF, and of the autonomic nervous system’s role in triggering and maintaining PAF, will allow more appropriate treatment of this condition.