Inferior-Lead Lambda (λ) Wave Revealing Critical Right Coronary Artery Stenosis: A Case Report

Ann Noninvasive Electrocardiol. 2026 Mar;31(2):e70169. doi: 10.1111/anec.70169.

Abstract

Lambda (λ) waves are uncommon ECG markers of malignant arrhythmias, usually associated with channelopathies or transient ischemia. We report a 34-year-old man with recurrent syncope preceded by subxiphoid chest pain and diaphoresis. Admission ECG showed λ-like morphology in the inferior leads with dynamic ST changes. Laboratory tests and echocardiography were normal, while Holter monitoring demonstrated persistent ST-segment depression. Coronary angiography revealed diffuse right coronary artery disease with a critical 95% stenosis, treated with drug-eluting stent placement. ECG abnormalities resolved after PCI, and syncope did not return. Serial angiography over 3.5 years confirmed sustained stent patency.

Keywords: case report; lambda wave; percutaneous coronary intervention; right coronary artery stenosis; syncope.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Coronary Angiography / methods
  • Coronary Stenosis* / complications
  • Coronary Stenosis* / diagnosis
  • Coronary Stenosis* / physiopathology
  • Coronary Stenosis* / surgery
  • Coronary Stenosis* / therapy
  • Drug-Eluting Stents
  • Electrocardiography* / methods
  • Electrocardiography, Ambulatory / methods
  • Humans
  • Male