Ventricular Aneurysm
Indications for Surgery
95 per cent of ventricular aneuryslns occur after transmural n~yocardial infarction. Tsa~una, Chaga's disease, sarcoidosis and congenital causes are the other aetiological factors. 85 per cent of then1 arc on the anterolateral wall of the LV, 5-10 per ccnt posterolatesally and less than 5 per cent are on the lateral wall.
The clinical presentation may be with congestive cardiac failurc, angina pectoris,ventricular arrl~ythmias, and dyspnoea or throinbo embolism. Rarely it could be asymptomatic. Diagilosis is confirmed by chest X-ray, ECG , ECHO and cardiac catheterization and LV and coronary aiigio. Special invesligalions like MRI, MUGA scan, thallium1 PET scan and electropl~ysiological study will be required in some cases before surgery.
In patients who have congestive heart failure, recurrent al-rllythmias or thrombo embolism and when investigations show ventricular aneurysm, surgery is indicated. Other patients with angina and LV aneurysm will require surgery for aneurysm along with bypass grafts if coronary atigio shows significanl blocks.Patients with aneurysm and moderate mitral regurgitation also have to be advised surgery along with milral valve repair.
A transmural infarct is the pre requisite for the fornlation of post infarction aneurysm. Total occlusion of LAD with poorly developed collaterals lead to extensive necrosis of muscle followed by thinning and aneurysm formation. The area becomes dyskinetic. The non aneurysmal poilion of the LV is subjected to increased systolic wall stress as ventricular size increases and ultimately loses its systolic reserve and contributes to LV failure. If there is multi vessel disease causing ischaenlia to the non-aneulysmal part of LV, the problem becomes worse.
Right vent~iculw function cogd be impaired after extensive antero septa1 infarct because of dyskinesia of the ventricular septum.Factors that determine survival are the size of aneurysm, severity and extent of coronary artery disease and the functional charactelistics of the remainder of the LV wall.
Types of Surgery
Classic Repair (Linear repair)
The operation is done under cardio puln~onary bypass, through median sternotomy. If additional CABG is required, conduit harvesting is done. The left ventricle should not be disturbed till the heart is arrested on cardio pulmonary bypass, to reduce the chances of embolisation of LV clot. Antegrade and retrograde cardioplegia are used. Bicaval cannulation and snaring of cavae is the prefened technique. Aneurysm is incised and opened vertically and all clots are removed. The thinned out portion of the aneurysm is removed leaving small margins where the normal muscle and the thinned out portions meet. LV cavity is irrigated with saline. Sutures are placed at the upper and lower ends of vertical ventliculotomy. Two strips of PTFE (poly tetrafluoro ethylene) felts are cut, the length depending on the final shape of the LV that is to be achieved. 2'0' polyester, double armed mattress sutures are passed incorporating both teflon felt ships and medial as well as lateral margins of opened LV After passing mattress sutures through the entire length of repair, they are tied. The lowest one near the apex is tied after filling LV and removing all air. Two layers of continuous polypropylene sutnres are used to reinforce the previous mattress sutures.
Thorough deairing of h e left heart and aortic root has to bc done before it is allowed to beat.If coronary artery bypass grafts have to be done, distal anastomoses are done before the repair of aneurysm. The proximal anastomoses arc done at the end after the release of aortic cross clamp.
Posterior Aneurysm
The technique of operation is the same. Care must be taken to avoid injury to the posterior papillary muscle and posterior descending coronary artery.
Associated Mitral Regurgitation
If significant MR is present, repair of the valve is done in the classical method by a left atrial approach. In elderly sick patient, an edge-to-edge rnitral valve repair (Alfieri) is done by a suture applied at the middle of the edges of anterior and posterior leaflets. This effectively makes a double orifice mitral valve and reduces prolapse and mitral regurgitation.
Results
In the present day, surgical mortality with or without CABG is repoi-ted to be 5-7 per cent. The late survival is 85 per cent, 75 per cent and 65 per cent at 1, 3 and 5 years respectively. Most long-term survivors have improved symptomatically and are in NYHA class I and 11.
False Left Ventricular Aneurysm
False aneurysm develops after acute rupture of a11 infasct. It is usually fatal, but a few survive because of previous adhesions between parietal pericardium and epicardium. The mouth is usually narrow and the aneulysin may expand and rupture. ?;hey occur more often on the diaphragmatic surface.
Doppler colour flow imaging and trans oesophaeal echocardiography help in diagnosing a false aneulysm.Resection is always recommended and carries higher risk than surgely for true aneurysm.
Indications for Surgery
95 per cent of ventricular aneuryslns occur after transmural n~yocardial infarction. Tsa~una, Chaga's disease, sarcoidosis and congenital causes are the other aetiological factors. 85 per cent of then1 arc on the anterolateral wall of the LV, 5-10 per ccnt posterolatesally and less than 5 per cent are on the lateral wall.
The clinical presentation may be with congestive cardiac failurc, angina pectoris,ventricular arrl~ythmias, and dyspnoea or throinbo embolism. Rarely it could be asymptomatic. Diagilosis is confirmed by chest X-ray, ECG , ECHO and cardiac catheterization and LV and coronary aiigio. Special invesligalions like MRI, MUGA scan, thallium1 PET scan and electropl~ysiological study will be required in some cases before surgery.
In patients who have congestive heart failure, recurrent al-rllythmias or thrombo embolism and when investigations show ventricular aneurysm, surgery is indicated. Other patients with angina and LV aneurysm will require surgery for aneurysm along with bypass grafts if coronary atigio shows significanl blocks.Patients with aneurysm and moderate mitral regurgitation also have to be advised surgery along with milral valve repair.
A transmural infarct is the pre requisite for the fornlation of post infarction aneurysm. Total occlusion of LAD with poorly developed collaterals lead to extensive necrosis of muscle followed by thinning and aneurysm formation. The area becomes dyskinetic. The non aneurysmal poilion of the LV is subjected to increased systolic wall stress as ventricular size increases and ultimately loses its systolic reserve and contributes to LV failure. If there is multi vessel disease causing ischaenlia to the non-aneulysmal part of LV, the problem becomes worse.
Right vent~iculw function cogd be impaired after extensive antero septa1 infarct because of dyskinesia of the ventricular septum.Factors that determine survival are the size of aneurysm, severity and extent of coronary artery disease and the functional charactelistics of the remainder of the LV wall.
Types of Surgery
Classic Repair (Linear repair)
The operation is done under cardio puln~onary bypass, through median sternotomy. If additional CABG is required, conduit harvesting is done. The left ventricle should not be disturbed till the heart is arrested on cardio pulmonary bypass, to reduce the chances of embolisation of LV clot. Antegrade and retrograde cardioplegia are used. Bicaval cannulation and snaring of cavae is the prefened technique. Aneurysm is incised and opened vertically and all clots are removed. The thinned out portion of the aneurysm is removed leaving small margins where the normal muscle and the thinned out portions meet. LV cavity is irrigated with saline. Sutures are placed at the upper and lower ends of vertical ventliculotomy. Two strips of PTFE (poly tetrafluoro ethylene) felts are cut, the length depending on the final shape of the LV that is to be achieved. 2'0' polyester, double armed mattress sutures are passed incorporating both teflon felt ships and medial as well as lateral margins of opened LV After passing mattress sutures through the entire length of repair, they are tied. The lowest one near the apex is tied after filling LV and removing all air. Two layers of continuous polypropylene sutnres are used to reinforce the previous mattress sutures.
Thorough deairing of h e left heart and aortic root has to bc done before it is allowed to beat.If coronary artery bypass grafts have to be done, distal anastomoses are done before the repair of aneurysm. The proximal anastomoses arc done at the end after the release of aortic cross clamp.
Posterior Aneurysm
The technique of operation is the same. Care must be taken to avoid injury to the posterior papillary muscle and posterior descending coronary artery.
Associated Mitral Regurgitation
If significant MR is present, repair of the valve is done in the classical method by a left atrial approach. In elderly sick patient, an edge-to-edge rnitral valve repair (Alfieri) is done by a suture applied at the middle of the edges of anterior and posterior leaflets. This effectively makes a double orifice mitral valve and reduces prolapse and mitral regurgitation.
Results
In the present day, surgical mortality with or without CABG is repoi-ted to be 5-7 per cent. The late survival is 85 per cent, 75 per cent and 65 per cent at 1, 3 and 5 years respectively. Most long-term survivors have improved symptomatically and are in NYHA class I and 11.
False Left Ventricular Aneurysm
False aneurysm develops after acute rupture of a11 infasct. It is usually fatal, but a few survive because of previous adhesions between parietal pericardium and epicardium. The mouth is usually narrow and the aneulysin may expand and rupture. ?;hey occur more often on the diaphragmatic surface.
Doppler colour flow imaging and trans oesophaeal echocardiography help in diagnosing a false aneulysm.Resection is always recommended and carries higher risk than surgely for true aneurysm.
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