Myocardial bridge and beta blockers: effect on left ventricular strain parameters.

OBJECTIVES: To assess the effect of beta-blocker treatment on left ventricular global longitudinal strain (LV Gls) as measured by echocardiography in patients with MB (Myocardial Bridge). PATIENTS AND METHODS: Between January 2019 and February 2022, a prospective, single-center study was undertaken in which myocardial bridging was identified in individuals who had coronary angiography. One hundred patients with myocardial bridging were systematically recruited and strain echocardiography was performed. Patient data were analysed in two groups - those who weren't using beta-blockers in the last six months (Group I: n = 50) vs. those who were (Group II: n = 50). RESULTS: One hundred patients participated in the study (38 females, 62 males; average age: 57.4 years). There was a statistically significant difference in the mean heart rate between groups I and II (p < 0.001). LV Gls was found to be statistically significantly improved in favour of group II when compared to group I [Group I: (-12.57)±3 vs. Group II: (-15.92)±2.9, p < 0.001]. CONCLUSION: The negative chronotropic effect of beta-blocker medication in individuals with MB identified by coronary angiography has a beneficial effect on LV Gls as measured by echocardiography.

Takotsubo syndrome early after treatment due to non cardiotoxic chemotherapy agents.

Takotsubo syndrome (TTS), acute stress-induced cardiomyopathy, is known to have a dramatic clinical presentation mimicking acute myocardial infarction. Recently developed chemotherapeutic drugs have resulted in improvements in morbidity and mortality in many forms of cancer. However, some chemotherapeutic drugs are cardiotoxic and may cause heart failure. Gemcitabine and vinorelbine are commonly used drugs for various solid organ neoplasms. While neither of these chemotherapeutic drugs has been directly associated with cardiotoxicity, there are a few case reports in the literature related to gemcitabine treatment- induced cardiomyopathy. This case report describes a case of TTS developing within hours of gemcitabine and vinorelbine chemotherapy.

Prevalence of inappropriate sinus tachycardia and the comparison of the heart rate variability characteristics with propensity score-matched controls.

OBJECTIVE: Inappropriate sinus tachycardia (IST) is a syndrome characterized by an elevated resting heart rate with distressing symptoms and no secondary cause of sinus tachycardia. This study was conducted to evaluate both the prevalence of IST among symptomatic patients and heart rate variability (HRV) characteristics. METHODS: The records of all consecutive symptomatic patients who had undergone 24-hour Holter monitoring between September 2015 and November 2016 at a single center were retrospectively evaluated. IST was defined as a 24-hour mean heart rate (HR) of ≥90 beats/minute and a resting HR of ≥100 beats/minute in the absence of any secondary cause of sinus tachycardia. All of the study data related to clinical characteristics, symptoms, concomitant diseases, and Holter electrocardiogram parameters were obtained from the electronic hospital records. A propensity age- and sex-matched control group was selected from a non-IST patient cohort. RESULTS: A total of 1865 consecutive patients were evaluated and 32% were excluded due to an inadequate Holter recording period or insufficient quality, atrial fibrillation episodes, atrioventricular block, or >1% atrial or ventricular extrasystoles. Among 1265 patients with sinus rhythm, 4.98% (n=63) had IST. The IST patients were younger (39.6±17.4 vs. 50.2±17.2 years; <0.001), and female gender was more prominent (60.3% vs. 43.8%; p=0.009). All of the time and frequency domain parameters of HRV except the low frequency/high frequency ratio were significantly reduced in the IST group compared with the propensity-matched controls. CONCLUSION: The IST prevalence among symptomatic patients in sinus rhythm was 4.98%. IST was primarily seen in younger women, and they had diminished time and frequency domain HRV parameters.