2024, Volume 31 (online first)

The combination of atrioventricular (AV) block – specifically high-grade AV block– within the setting of myocarditis, is a rarely encountered clinical phenomenon. It is commonly encountered in infiltrative cardiomyopathies but may be associated with myocarditis.

Beyond conventional investigation and consideration of endomyocardial biopsy, there is a paucity of data to guide clinicians with regards to the issue of heart rhythm disorder. Options include a ‘watch-and-wait’ policy, anti-arrhythmic drugs, consideration of a permanent pacemaker or, alternatively, a wearable or implantable cardioverter-defibrillator (ICD).

The case encapsulates the difficulties facing clinicians with such pathology and the need to further investigate and risk stratify such patients.

Endomyocardial fibrosis is a common cause of restrictive cardiomyopathy worldwide, but rarely occurs in patients living outside tropical regions.¹ Herein is the first published case report of a 48-year-old woman with endomyocardial fibrosis due to hypereosinophilia secondary to a rare chromosome 8 and 9 PCM1-JAK2 translocation.

A 74-year-old man with a heterotopic heart transplant experienced alternating episodes of sustained native heart ventricular tachycardia and prolonged asystole. These were managed with cardioversion, drug therapy and pacemaker insertion. The unique physiology in such patients lends itself to numerous clinical considerations that would otherwise be routine management for most.

A young man with multifocal cavitating pneumonia presented with early abscess formation secondary to Staphylococcus aureus bacteraemia treated with intravenous (IV) flucloxacillin. Further workup with transthoracic echocardiography revealed a large vegetation on the tricuspid valve with at least moderate tricuspid regurgitation; however, there were no peripheral stigmata of infective endocarditis. There was no history of intravenous drug use, but he had a history of administering frequent intramuscular recreational steroid injections. He also had a recent history of a loose tooth. In addition, there were multiple skin excoriations from scratching related to anxiety. Transoesophageal echocardiography confirmed two vegetations on the tricuspid valve, the largest measuring 21 mm with evidence of severe tricuspid regurgitation. The findings were discussed in the cardiac surgery multidisciplinary meeting and the consensus was for initial sterilisation with IV antibiotics followed by surgery.

This case report explores the effects of myocarditis induced by coronavirus disease 2019 (COVID-19) on a cardiac implanted electronic device (CIED) and its ability to differentiate depolarisation and repolarisation. Through the modification of the device settings, inappropriate CIED discharges were prevented for the duration of the illness in this 76-year-old male patient. This provides supporting evidence to consider episodes of acute COVID-19 as a cause for T-wave oversensing (TWOS).

Subclavian venoplasty is commonly performed for subclavian vein stenosis in patients with long-term dialysis lines or fistulae. Such stenosis may also occur in patients with previously implanted intra-cardiac devices. It poses a problem if a further device upgrade or implantation is planned as the stenosis restricts the advancement of leads. Venoplasty before device implantation may provide a feasible alternative to lead tunnelling or extraction, which have their limitations. Four cases of varying complexities and devices that were implanted in patients with subclavian stenosis are presented herein. These were done in a district general hospital within the cardiology team. Venoplasty was performed using peripheral angioplasty balloons after which the device was implanted. All cases were performed successfully without any immediate complications with the patients discharged home the same day. These cases show the utility of subclavian venoplasty in facilitating device implantation without the need to utilise contralateral venous access, hence preserving venous access for the future. Additionally, they illustrate that this may be performed locally in a district general hospital setting, where appropriate expertise is available, with a high success rate and without the need to refer patients to an alternate tertiary care institute which may be associated with additional difficulties for the patient. To the best of our knowledge, this is the first instance where several cases of this procedure were performed successfully in a secondary care setting.

Pathogenic genetic variants in the HCN4 (hyperpolarisation-activated and cyclic nucleotide-gated channel) gene can cause sinus node dysfunction, disrupting the function of the pacemaker region of the heart. Patients with such variants can present with a wide spectrum of arrhythmias but sudden death is generally considered rare. We report two cases from the same family with different outcomes to highlight a potential high-risk phenotype in HCN4-related disease.

A 59-year-old woman presented to the emergency room with sudden onset of retrosternal thoracic pain following emotional stress. The electrocardiogram (ECG) revealed T-wave inversions on precordial leads. Her blood analyses demonstrated elevation of myocardial necrosis markers (peak of troponin I of 3.4 ng/ml). Transthoracic echocardiogram (TTE) findings were consistent with Takotsubo syndrome, accompanied by mild left ventricular dysfunction. The patient underwent invasive coronary angiography revealing a spontaneous coronary artery dissection in the left anterior descending artery and left main artery. A repeat TTE one week later showed complete resolution of the segmental contractility with a full recovery of left ventricular function. Cardiac magnetic resonance imaging revealed no abnormalities. The patient was discharged on dual-antiplatelet therapy. A follow-up coronary angiography performed one month later confirmed complete resolution of the dissection. Takotsubo syndrome and spontaneous coronary artery dissection predominantly affect women and share common triggers. This case highlights the often misdiagnosed association and emphasises the specific diagnosis and treatment nuances associated with it.

Cardiac metastases normally reflect diffuse metastatic spread of the primary tumour and are rarely found in isolation. We present a case of a 71-year-old man with a history of completely resected high-grade spindle cell sarcoma of the left thigh, who presented with shortness of breath, and was found to have a large right ventricular mass, subsequently diagnosed as a metastasis of the prior sarcoma. It was deemed inoperable and incurable, and the patient was offered palliative chemotherapy. Unfortunately, the patient died within four months of his original presentation.