JACC Case Rep. 2026 Sep 29:110741. doi: 10.1016/j.jaccas.2026.110741. Online ahead of print.
ABSTRACT
BACKGROUND: In patients with multiple primary malignancies, an intramyocardial mass poses a diagnostic challenge when its perfusion pattern deviates from classic metastatic profiles.
CASE SUMMARY: A 58-year-old man with prior renal cell carcinoma (RCC) and nasopharyngeal carcinoma presented with progressive chest distress and dyspnea. Transthoracic echocardiography revealed a 43 × 34 mm right ventricular apical mass supplied by the distal septal branch of the left anterior descending artery. Myocardial contrast echocardiography (MCE) demonstrated delayed filling and slow sustained enhancement. Positron emission tomography/computed tomography showed no systemic disease. Partial resection confirmed metastatic RCC. At the 3-month follow-up, the patient was clinically stable.
DISCUSSION: This case reveals a discordance between macrovascular and microvascular perfusion, representing an imaging pitfall. MCE excluded thrombus and characterized atypical perfusion. In double primary malignancies, multimodality imaging guided differential diagnosis.
TAKE-HOME MESSAGES: Transthoracic echocardiography can identify feeding arteries of an intramyocardial mass despite recognized limitations. Atypical perfusion kinetics on MCE does not exclude RCC metastasis; multimodality imaging should be considered in patients with double primary malignancies.
PMID:42886132 | DOI:10.1016/j.jaccas.2026.110741