Seasonal variation of takotsubo cardiomyopathy

Climatic variables in Takotsubo cardiomyopathy: role of temperature

BACKGROUND

Recent studies documented a seasonal (summer) and circadian (morning) temporal distribution of takotsubo cardiomyopathy (TTC).

AIM

The aim of our study was to investigate whether there is a relationship among season, temperature and the occurrence of TTC. A second aim of our study was the comparison of climatic variables in Takotsubo cardiomyopathy versus acute myocardial infarction (AMI).

METHODS

We enrolled consecutive patients with TTC in three Italian centres and, for comparison consecutive patients with AMI. The frequency of TTC and AMI patients according to month, season and quartiles of temperature (I quartile: 9.8-15°, II quartile: 15-19°, III quartile: 19-25° and IV quartile: 25-38°C) was reported. Climatic variables of TTC and AMI patients were compared.

RESULTS

We included in the study 85 patients with TTC and 900 patients with AMI. It was not observed a significant peak in the occurrence of TTC during summer time; however, when compared with AMI, TTC was more frequent in summer. We found an absolute higher frequency of TTC cases with warmer temperatures. TTC cases occurred during warmer temperatures than AMI.

CONCLUSION

Our study does not confirm a summer preference for TTC occurrence, as reported by previous studies, even if, compared with AMI, TTC is more frequent in summer. During warmest days, it was recorded the highest incidence of TTC.

Epidemiology and clinical profile of Takotsubo cardiomyopathy

First described in Japan over 2 decades ago, takotsubo cardiomyopathy (TTC) has emerged as a unique cardiomyopathy with world-wide recognition, mimicking acute coronary syndrome. In early TTC experience, typical patients were older women, with a triggering emotional event, ST-segment elevation, and apical ballooning left ventricular (LV) contraction pattern. However, TTC is now more heterogeneous, occurring in males and younger individuals, without ST-segment elevation, as a spontaneous event in the absence of a trigger, and with diverse LV contraction patterns. Furthermore, TTC is more common than initially thought, now constituting 10% of women with suspected acute coronary syndrome. TTC is also associated with a broader range of psychological or physical triggers, including presentation during outpatient medical evaluations or hospitalization for acute illness. Although TTC has been considered a benign condition, it now carries a small but important risk for adverse outcomes, including cardiac arrest in 5%. Hemodynamic instability requiring intervention with vasopressor drugs or intra-aortic balloon pump is necessary in 15% and in-hospital mortality is approximately 5%, largely because of refractory cardiogenic shock or irreversible major comorbid conditions. Although complete cardiac recovery usually occurs rapidly, post-hospital survival may be less than the general population of similar age, largely because of concomitant illnesses. TTC may reoccur in up to 10% of patients, but β-blocking drugs are not absolutely preventive for initial or subsequent events.

Burden of arrhythmias in patients with Takotsubo cardiomyopathy (apical ballooning syndrome)

INTRODUCTION

The objective of our study was to assess the burden of arrhythmias, the gender differences in occurrence of arrhythmias and the impact of these arrhythmias on hospitalization outcomes in patients with Takotsubo Cardiomyopathy (TTC).

METHODS

TTC and various arrhythmias were identified using appropriate ICD-9-CM codes from Nationwide Inpatient Sample (NIS) discharge records 2006-2010. Length of hospital stay (LOS), in-hospital mortality and total charges were used to assess the impact of the arrhythmias on TTC hospitalization. All analyses were performed using SASv9.2 (Cary Institute Inc., Cary, NC).

RESULTS

A total of 16,450 patients were included in the study and 26% (n=4296) of patients had cardiac arrhythmias. Following arrhythmias were present in the descending order of frequency: atrial fibrillation (Afib) 6.9%, ventricular tachycardia (VT) 3.2%, atrial flutter (Afl) 1.9%, ventricular fibrillation and flutter 1%, paroxysmal supraventricular tachycardia (PSVT) 0.8%. Nearly two percent of the patients had sudden cardiac arrest (SCA). Males were more likely to have cardiac arrhythmias in general compared to females (OR: 1.5, 95% CI: 1.3-1.7, p-value 0.001). Occurrence of ventricular tachycardia (OR: 1.7, 95% CI: 1.3-2.2, p-value<0.001) and sudden cardiac arrest OR: 1.6, 95% CI: 1.1-2.2, p<0.001) were significantly higher in males. In contrast, Afib was significantly less in males compared to females (OR:0.8, 95% CI:0.6-0.9). Patients with arrhythmias had significantly longer length of stay, and increased cost of hospitalization and mortality.

CONCLUSIONS

Arrhythmias are present in nearly one-quarter of patients with TTC and worsen the outcome. While TTC has been established as a disease mainly of females, life threatening arrhythmias like VT and SCA are more common in males.