Midterm survival following repair of a giant left ventricular true aneurysm ruptured during operation and associated with papillary muscle rupture/Papiller adele rupturu ile birlikte gorulen ve operasyon sirasinda rupture olan dev sol ventrikul gercek anevrizmasinin onarimi sonrasi orta donem yasam suresi.

Introduction

Left ventricular (LV) aneurysm is a common complication of myocardial infarction. The most common type of aneurysm is a true aneurysm, which forms after transmural infarction by gradual thinning and expanding of the scarred left ventricular wall (1). In an autopsy series of patients of deaths from acute myocardial infarction (AMI), cardiac rupture was present in 30.7% patients, with LV rupture in 98% (anterior wall 45%, posterior wall 38%, lateral wall 9% and apex 6%) and right ventricular rupture in 2% (2). Also papillary muscle rupture (PMR) is usually seen 2-9 days after the infarction and causes serious hemodynamic instability, cardiogenic shock and pulmonary edema with mitral regurgitation (3).

True LV aneurysm and PMR following AMI is a rare but fatal clinical case. So, in addition to coronary artery bypass grafting (CABG), surgical resection of ventricular aneurysm must be performed for treatment (4).

We reported a case of a 62-year-old man who underwent emergency surgical repair of a giant LV aneurysm ruptured during operation and associated with PMR following AMI.

Case report

The patient was a 62-year-old man who was admitted to our hospital with chest pain and symptoms related to acute heart failure and pulmonary oedema. Coronary angiography revealed proximal lesions and a poor distal run-off of left anterior descending artery (LAD), circumflex artery (Cx) and right coronary artery (RCA). Left ventriculography could not be applied since the patient has pulmonary edema. Left ventricular dimensions were larger, basal and middle segments of posterior and lateral wall were akinetic and there was a giant (5.8 x 4.3 cm) LV aneurysm, which was localized posterolaterally with echocardiographic investigation (Fig. 1). Myocardial thickness of aneurysmatic area was thinner (0.5 cm). Also transthoracic echocardiography revealed, 3- 4[degrees] mitral regurgitation, PMR and 14 mm of coaptation difference between anterior and posterior mitral leaflets. Effective regurgitant orifice area (EROA) was 0.41 cm2 and regurgitant volume was 85 ml by echocardiographic evaluation.

After preoperative evaluation, intraaortic balloon pump inserted because of pulmonary edema and poor left ventricular functions. During operation a true aneurysm with a size of 5.8 x 4.3 cm was observed posterolaterally at the left ventricle. Aneurysm was ruptured during aorto-bicaval cannulation so emergency cardiopulmonary bypass was established. The rupture was then securely repaired by using an endoventricular circular patch plasty technique. Ventricle was then closed by using Teflon feld.

After this process, LAD-left internal mammarian artery-Aorta, Obtuse Marginal 1-Saphenous vein-Aorta, RCA-Saphenous vein-Aorta bypasses were performed. Then, left atrium was opened and mitral valve was exposed. Since subvalvular apparatus remains in the repaired aneurysmatic area, mitral valve was not convenient for repair and mitral valve replacement (MVR) operation was applied by using bi-leaflet mechanical mitral valve (No: 27).

[FIGURE 1 OMITTED]

The patient tolerated the procedure uneventfully and was weaned from cardiopulmonary bypass easily with minimal inotropic support. He was discharged on the tenth postoperative day. The control echocardiography 1 month after the operation showed a satisfactory result (Fig. 2). At his 16th month follow up patient has no symptoms.

Discussion

Left ventricular aneurysm and PMR are serious complications of AMI. True LV aneurysm occurs months or years after AMI, infrequently undergoes progressive and rapid expansion or rupture and contains three layers of myocardium (5). In general, LV aneurysms are located anterolaterally near the apex. Few are confined to the lateral area and posterior, near the base of the heart. True LV aneurysm rupture is infrequent but has a high rate of mortality.

Surgical repair of the rupture site is the definitive treatment for cardiac rupture, although there are few data on operative mortality rates. Lopez-Sendon and colleagues reported an immediate operative mortality rate of 24% and a hospital mortality rate of 52% (6). Other reports listed the operative mortality rate as 24% to 35% (7). These mortality rates are high, but probably the true mortality is underestimated because numerous cases of attempted repair resulting in death are likely unreported. Long-term survival has been accomplished with surgical repair, and this may become more common as clinical predicting factors and early diagnosis are better established, allowing earlier attempts at surgical repair.

Papillary muscle rupture associated with giant LV aneurysm following AMI is rare according to the previous investigations. Killen et al. reported that 16 patients underwent MVR for PMR after AMI and one of these had resection of an associated LV aneurysm (8). Also, the combination of septal perforation, impending cardiac rupture of LV aneurysm and PMR after AMI has been reported by Thalele et al. (9). Veinot et al reported a study of twenty-five consecutive patients with left ventricular free wall rupture between 1988 and 1992. Each patient died of tamponade or after surgery for tamponade. In 15 of 25 (60%) cases, free wall rupture occurred in the lateral wall between and at the level of the two papillary muscles. In further 5 of 25 (20%) cases, the rupture was besides one of the papillary muscles but in anterior or posterior walls. In 20 of 25 (80%) cases, the endocardial tear associated with the left ventricular free wall rupture was within 1 cm of the base of one of the papillary muscles as they inserted in left ventricular free wall. Asymmetric papillary muscle contraction forces in the area of the infarct may play a role in the genesis of left ventricular free wall rupture as most ruptures appear in close association to the papillary muscle insertions in the left ventricular free wall (10).

[FIGURE 2 OMITTED]

In conclusion, there are few case reports as a giant posterolateral LV aneurysm combined with PMR following AMI. Mortality of these cases is high after the procedure of coronary bypass surgery associated with MVR and aneurysmectomy. We present this case because of the midterm survival (16 months) after operation in spite of the rupture of giant aneurysm during operation.

References

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(3.) Kishon Y, Oh JK, Schaff HV, Mullany CJ, Tajik AJ, Gersh BJ. Mitral valve operation in postinfarction rupture of a papillary muscle: immediate results and long-term follow-up of 22 patients. Mayo Clin Proc 1992; 67: 1023-30.

(4.) Froehlich RT, Falsetti HL, Doty DB, Marcus ML. Prospective study of surgery for left ventricular aneurysm. Am. J. Cardiol 1980; 45: 923-31.

(5.) Pontone G, Andreini D, Ballerini G, Pompilio G, Alamanni F, Nobili E et al. An unusual case of large left ventricular aneurysm: Complementary role of echocardiography and multidetector computed tomography in surgical planning. Eur J Radiol Extra 2005; 54; 51-4.

(6.) Lopez-Sendon J, Gonzalez A, Lopez de Sa E, Coma-Canella I, Roldan I, Dominguez F et al. Diagnosis of subacute ventricular wall rupture after acute myocardial infarction: sensitivity and specificity of clinical, hemodynamic and echocardiographic criteria. J Am Coll Cardiol 1992; 19: 1145-53.

(7.) Pollak H, Diez W, Spiel R, Enenkel W, Mlczoch J. Early diagnosis of subacute free wall rupture complicating acute myocardial infarction. Eur Heart J 1993; 14: 640-8.

(8.) Killen DA, Reed WA, Wathanacharoen S, Beauchamp G, Rutherford B. Surgical treatment of papillary muscle rupture. Ann Thorac Surg 1983 Mar; 35: 243-8.

(9.) Tahalele P, Prasmono A, Puruhito I, Prayitno BW, Rahardjo P, Adipranoto J et al. Surgical repair of an impending rupture of left ventricular (LV) aneurysm with septal perforation and rupture of papillary muscle after acute myocardial infarction. Ann Thorac Cardiovasc Surg 2000; 6: 401-4.

(10.) Veinot J.P, Walley V.M, Wolfsohn A.L, Chandra L, Russell D, Stinson WA, et al. Postinfarct cardiac free wall rupture: The relationship of rupture site to papillary muscle insertion. Modern Pathol 1995; 8: 6: 609-13.

Mehmet Cakici, Bahadir Inan, Sadik Eryilmaz, Mustafa Sirlak, Umit Ozyurda Department of Cardiovascular Surgery, School of Medicine, Ankara University, Ankara, Turkey

Address for Correspondence/Yazisma Adresi: Dr. Mehmet Cakici, Department of Cardiovascular Surgery, Heart Center, Ankara University School of Medicine, Dikimevi, 06340, Ankara, Turkey Phone: [phone] Mobile: [phone] E-mail: [e-mail], [e-mail]