Capecitabine-induced ventricular fibrillation arrest: Possible Kounis syndrome

The Descriptive and Disproportionality Assessment of EudraVigilance Database Reports on Capecitabine Induced Cardiotoxicity

Capecitabine (CAP) is one of the most commonly prescribed fluoropyrimidines in oncology, especially in the treatment of colon cancer. Cardiac toxicity is a severe and potentially lethal adverse drug reaction (ADR) against fluoropyrimidines. Cardiac ADRs, such as myocardial infarction (MI), heart failure (HF), arrhythmias, and a number of cardiomyopathies, are reported for these molecules. To have a better understanding of the risk-benefit ratio of colon cancer therapy, a pharmacovigilance study of real-world evidence of the cardiac toxicity of antineoplastic agents is required.

AIM

This post-marketing research on CAP aims to assess the risk of cardiac toxicity. Five other antitumor drugs used in colorectal cancer, i.e., 5-fluorouracil (5-FU), irinotecan (IRI), oxaliplatin (OX), bevacizumab (BEV) and panitumumab (PAN), were also studied to create a relative profile of observed cardiotoxicity.

METHODS

A retrospective study based on reports submitted in the EudraVigilance (EV) database until 28 July 2024 was conducted. Using the aggregated data from EV, a descriptive analysis and disproportionality analysis of cardiac ADRs induced by fluoropyrimidines were performed. To evaluate the disproportionality of the signals, Reporting Odds Ratio (ROR) and 95% confidence interval (95% CI) were calculated by comparison with other drugs used in colorectal cancer: 5-FU, IRI, OX, BEV, and PAN.

RESULTS

"Cardiac disorders" represent 3.4% of the total reports for CAP. The value is comparable to 5-FU, but higher than for other drugs. t was observed that there are no significant differences in the occurrence of cardiac ADRs in patients exposed to CAP and 5-FU treatments, and in particular MI and HF. Compared to 5-FU, which could produce cardiac arrythmias with a higher probability than all other drugs, CAP has a higher probability of reporting this ADR only in comparison with IRI (ROR: 1.2971; 95% CI: 1.0196-1.6502).

CONCLUSIONS

CAP induces adverse cardiovascular reactions, especially MI, HF, and cardiomyopathies. Arrhythmias have been shown to be side effects more frequent associated with 5-FU than with CAP. The results emphasize the need for a rigorous cardiovascular monitoring of patients following treatment with CAP or 5-FU and especially for those with pre-existing cardiac pathology.

Exploring Variations in Etiology and Clinical Presentations of Kounis Syndrome Across Pediatric and Adult Populations: A Comprehensive Review

Kounis syndrome (KS), recognized as a rare yet significant form of acute coronary syndrome precipitated by allergy-mediated mechanisms, poses diagnostic challenges due to its varied clinical presentations and under-recognition. Despite its relevance across diverse populations, comprehensive insights into age-specific characteristics and management remain limited. The analysis of 420 studies yielded a total of 466 case reports of Kounis syndrome, categorized into pediatric (n = 31) and adult (n = 435) populations. After rigorous screening, 330 adult and 20 pediatric case reports were included for further analysis. Triggering factors were identified, with drugs (other) being the most prevalent in both groups. The breakdown of triggering factors, such as drugs (antibiotics), bee/wasp stings, and contrast media, was elucidated. Variations in presenting symptoms, diagnostic investigations, and treatment modalities between pediatric and adult populations were observed. Notably, all pediatric cases were diagnosed with subtype I Kounis syndrome and demonstrated favorable outcomes without any reported fatalities, whereas adult cases exhibited a broader range of Kounis subtypes. Mortality was recorded solely in adult case reports, with no fatalities reported among pediatric cases. These findings underscore the importance of understanding the nuances in the clinical presentation and management of Kounis syndrome across different age groups.

Kounis Syndrome: Review of Clinical Cases

BACKGROUND

Kounis syndrome is defined as a combination of acute coronary syndrome and allergic reactions.

OBJECTIVE

In this review, we aim to describe the etiological, clinical, and diagnostic characteristics of Kounis syndrome.

METHODS

A literature search using PubMed was conducted for the past 32 years using keywords, resulting in the selection of 761 scientific papers. From these, 217 articles describing 235 clinical cases were selected. Patients under 18 years of age or without a confirmed diagnosis were excluded.

RESULTS

Among the 235 patients, type I Kounis syndrome was observed in 49.7%, type II in 27.2%, type III in 5.9%, and a combination of types I and II in 1.0%; in 16.2%, it was not possible to classify the type of Kounis syndrome. The median age was 57 years, and 68.5% of the patients were male. The most common causes were antibiotics (32.3%) and non-steroidal anti-inflammatory drugs (24.3%). The clinical features included chest pain (59.1%), hypotension (74.2%), itching (30.6%), and dyspnea (30.6%). Electrocardiographic monitoring revealed ST-segment elevation in 42.9% and was normal in only 5.5% of patients. Coronary angiography was performed in 80.4% of the patients, revealing unchanged coronary arteries in 50.3% of cases. Сonclusion: Allergic myocardial infarction is a serious complication of drug therapy.

Capecitabine-Associated Coronary Vasospasm and Cardiac Arrest

Capecitabine is a prodrug of fluorouracil that specifically targets cancer cells, commonly used as monotherapy for metastatic breast and colorectal cancer. Its side effects include nausea, diarrhea, vomiting, abdominal pain, anorexia, palmar-plantar erythrodysesthesia, anemia, and hyperbilirubinemia. Rarely, this chemotherapy agent has been associated with cardiotoxicity, including cardiac arrest, likely secondary to coronary vasospasm. This case report serves to highlight the unfortunate case of a 32-year-old female who suffered a ventricular fibrillation cardiac arrest three days after initiating capecitabine therapy.

Successful 5-fluorouracil (5-FU) infusion re-challenge in a metastatic colorectal cancer patient with coronary artery disease who experienced symptoms consistent with coronary vasospasm during first 5-FU infusion

5-fluorouracil (5-FU) is an important component of chemotherapy for metastatic colon cancer and can be administered as an intravenous infusion or bolus. Coronary vasospasm is a known complication of infusional and bolus 5-FU administration. In patients who experience coronary vasospasm, 5-FU is often discontinued. Several cases of successful re-challenge with bolus 5-FU, utilizing calcium channel blockers (CCBs) and nitrates to prophylaxis against coronary vasospasm recurrence, have been reported in the literature. However, since there is increased variability of time to symptom onset with infusional 5-FU, re-challenge with infusional 5-FU has not been widely studied. Given potential differences in the toxicity profile and exposure time, infusional may be more appropriate than bolus for some patients. Here we report successful re-challenge with infusional 5-FU, following coronary vasospasm during the first cycle of 5-FU plus leucovorin plus oxaliplatin chemotherapy, in a patient with metastatic colon cancer and coronary artery disease (CAD). The 5-FU re-challenge plan included dose reduction, CCB and nitrate prophylaxis, and telemetry monitoring.