<p>One variant of postinfarction ischaemic cardiomyopathy is a dyskinetic or akinetic left ventricular aneurysm. Lateral localisation of the postinfarction aneurysms in the interpapillary space is an extremely rare pathology. As a rule, in postinfarction aneurysms of this localization, intracavitary thrombosis develops with large aneurysm sizes or the formation of a false aneurysm. However, thrombus formation in the area of small aneurysms or postinfarction scar of the sidewall, as observed in our case, is extremely rare.<br />This report describes an extremely rare case of the surgical treatment of thrombosis of the posterior-lateral wall of the left ventricle involving the base of the posteromedial papillary muscle.<br />A 59-year-old man was admitted to the hospital with complaints of weakness and shortness of breath under minimal load. He had experienced a heart attack 5 y previously, as per his coronary angiography and had a multi-vessel lesion of the coronary arteries. According to the results of electrocardiography-scarring changes along the posterior wall of the left ventricle, transthoracic echocardiography-dilation of the left heart, a decrease in the ejection fraction of the left ventricle, akinesia of the posterior and posterolateral walls with floating thrombosis of this zone. Surgical intervention was performed under conditions of cardiopulmonary bypass and pharmaco-cryocardioplegia. The heart cavity was opened with left-sided ventriculotomy along the posterior wall, along the interventricular septum. A blood clot was removed with the excision of the lining area along the posterior-lateral wall. Plastic surgery was performed to isolate the scarred myocardium with a Dacron patch; thereafter, reconstruction of the posterior left ventricular wall was performed with a second patch. Plastic surgery of the posterior wall of the left ventricle was performed. The last stage was performed via coronary bypass surgery of the anterior interventricular artery. The duration of stay in the intensive care unit was 20 h, and the duration of hospitalisation was 9 d. He was discharged in the state corresponding to the Class I–II (New York Heart Association Functional Classification, NYHA).<br />Patients with thrombosed left ventricular aneurysms need surgical treatment, irrespective of the localization of the process for de-escalation of the thrombogenic zone and restoration of the ventricle geometry. However, the choice of surgery is clinically challenging and depends on a deep understanding of the anatomical relationships in the left ventricle as well as the prediction of a positive transformation after left ventricular reconstruction. Despite our extensive experience in the treatment of postinfarction aneurysms, this was the first time we treated a patient with an unusual location of a blood clot.</p><p>Received 17 April 2020. Revised 28 May 2020. Accepted 3 June 2020.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong><br />Participation in the operation: M.D. Alshibaya, M.M. Amirbekov, Z.M. Cheishvili, O.S. Lagutina, I.V. Slivneva<br />Conception and design: M.D. Alshibaya, I.V. Slivneva<br />Drafting the article: M.D. Alshibaya, I.V. Slivneva, M.M. Amirbekov, Z.M. Cheishvili, O.S. Lagutina<br />Critical revision of the article: M.D. Alshibaya, I.V. Slivneva, M.M. Amirbekov <br />Final approval of the version to be published: M.D. Alshibaya, I.V. Slivneva, M.M. Amirbekov, Z.M. Cheishvili, O.S. Lagutina</p>
