Heart attacks management

 Important steps in the management of heart attack

1.     Oxygen inhalation

2.     Aspirin is an important medicine in the treatment of heart attack. Aspirin alone in dose 160 mg per day may reduce fatality by 21% and if aspirin and streptokinase are both used mortality can be reduced by 39%. Aspirin should be started as soon as the patient is admitted and given daily until discharged from the hospital, at which time it can be continued at a dose of 75 mg to 325 mg daily in absence of any specific contraindication.

3.     Nitroglycerine: either by mouth or through intravenous infusion.

4.     Morphine for relief of chest pain.

5.     Beta blockers for prevention of recurrent heart attack and sudden death.

6.     Angiotensin converting enzyme inhibitors for prevention of ventricular remodeling (heart dilatation).

Heart Transplant, TMR, Endarterectomy, Keyhole Surgery of bypass operations

New operative techniques  of Bypass Operations 

1.     Endarterectomy:

 During surgery removal of atheroma by opening the coronary artery is called endarterectomy. This procedure is sometimes utilized with CABG operation and may ensure good results.

2.     TMR: 

TMR represents a novel approach to treat coronary disease. In this procedure Laser is used to create or drill 15 to 30 channels approximately 1 mm in diameter in left ventricular wall. After TMR, an oxygen-starved area of heart gets direct contact with the oxygen rich blood in the chamber.

3.     Cardiac transplantation:

 The first human heart transplant was performed by a South African cardiac surgeon, Dr. Christian Bernard in South Africa in 1967. Cardiac transplantation is presently the optimum surgical treatment for severe end stage heart failure. Allograft transplantation results in 90% survival at one year and 50% survival at five years with return to a near normal quality of life.

4.     Cardiomyoplasty: 

In this technique severely failed heart is wrapped by chest muscle named Latissimus Dorsi. This muscle is then driven electrically which helps the heart in pumping. But this operation coats around 30% mortality in the first year.

5.     Reshaping the heart: 

Reduction of left ventricular volume by resecting a part may increase longevity. In this technique large part of the left ventricle is removed and size of the heart is reduced. Though this operation somehow improves the quality of life but this procedure carries 15% risk of death during operation.

6.     Artificial Heart: 

This is a new technique which showed promise in the surgical treatment of heart failure. The Jarvik 2000, is a pump, about the size of a thumb designed to sit within the apex of the heart and silently deliver non-pulsatile flow rates up to 10 liters per minute. In animal models it has shown excellent performance.

7.     Keyhole Surgery:

 This technique is one of the biggest achievements in the history of cardiac surgery. By using this technique surgeons can now perform bypass surgery through a simple three-inch incision. In a standard CABG operation, surgeons sever the patient’s breastbone with a saw; open the rib cage with a steel retractor  then stop the heartbeat while they reconfigure its supporting blood vessels. But in new technique surgeons make a small incision “Keyhole” between the ribs. This operation can be done when the heart is still beating and stopping the heart is optional. Patient may be discharged after three to five days and the patients are fit to play golf two weeks later. But this new technique will not eliminate open heart surgery. This procedure is intended mainly for single vessel bypass operations which are less common. So if the patient requires more than one bypass, may be possible through the keyhole operation.

8.     MIDCAB and OPCAB: 

These surgical strategies include surgery through small incisions or surgery without cardiopulmonary bypass or some combination of two. By pass on beating heart “off pump” bypass surgery through a small median sternotomy incision is the most widely used procedure now a day. “Off-pump” surgery through small incision is most commonly employed as a left internal mammary artery to the left anterior descending artery graft through a left anterior thoracotomy. Robotics technology, still in its infancy, offers the possibility of expanding access to coronary arteries “off-pump”.

9.     Hybrid operation: 

The concept of adjunctive coronary angioplasty combined with minimally invasive bypass surgery for revascularization of multivessel coronary artery disease has been developed in recent years. This minimally invasive bypass surgery has obviated the risks of median sternotomy and cardiopulmonary bypass procedure. Patients earlier considered high risk for a conventional CABG operation, are now candidates for surgical revascularization by the less invasive surgery. The hybrid operation is nothing but a combination of PTCA and CABG simultaneously on a same patient. This combined strategy of mini CABG and balloon angioplasty is extremely useful if used judiciously in appropriate high risk patients.  

Treatment Coronary Artery Disease

New techniques in the treatment of coronary artery blockage

1.     atherectomy2.     rotational ablation3.     laser balloon angioplasty

Atherectomy: This is the process of extraction of the cholesterol rich plague or blockage from the coronary artery. This is also introduced inside body through the groin and it also looks like a balloon catheter. The blockages are cut into pieces and are stored inside a small housing. The conventional balloon PTCA can not reduce the bulk of the blockage but only compress it. During atherectomy the bulk of the atheroma can be reduced, so it is a debulking procedure. There is cutting blade at the tip of the catheter and it spins at a rate 5000 rpm inside the coronary artery. Though this type of treatment can reduce the size of the blockage more effectively and produce lumen diameters better than PTCA but these new techniques have not reduced the rates of acute complications or restenosis after coronary angioplasty.

Rotational ablation: This is another approach for removing atheromatous plaque from the narrowed coronary arteries. It looks like a burr and the whole process can be compared with burring usually performed by the carpenters. This technique uses a diamond studded burr spinning at about 180000 rpm to excavate the obstruction. Though burring is associated with higher short-term success but the rates of restenosis is higher in burring patient compared to conventional PTCA.

Laser balloon angioplasty: the present technique involve the application of a continuous wave neodymium, yttrium laser irradiation transmitted through a fiberoptic system that heats up the culprit obstruction. Argon laser, Holmium laser are also used to reduce the blockage. This technique did not gain popularity as long term results are disappointing.

Coronary Stent

Coronary stent

The long-term benefit of conventional coronary angioplasty is limited by the possibility of restenosis (reocclusion) of the treated artery, which occurs in approximately 30 to 50% of patients. Preliminary evidence suggests that stents may reduce the chance of restenosis by decreasing the elastic recoil of the vessel and sealing internal flaps, thus providing a wider, smoother coronary lumen. The first human coronary stenting was done by Sigwart et al in 1987.