Manoj Bharathiraja: What causes a cardiac arrest right after bypass surgery?

Tamil actor-director Manoj Bharathiraja died of a cardiac arrest on Tuesday, at the age of 48. As per reports, he had undergone a coronary artery bypass surgery last week and had returned home from the hospital. However, he had a cardiac arrest within a few days after the surgery. The Germany-based Journal of Cardiothoracic Surgery say it is a serious complication with a low survival rate, though it is uncommon, with an incidence of 0.7 to 2.9%. The National Institute of Health explains that such a cardiac arrest can be attributed to many reasons, which are:
1) Acute graft occlusion
This is a situation in which a sudden block develops in a bypass graft (the new blood vessel surgery used to bypass a blocked artery). Blood clots, plaque buildup, poor blood flow, and other causes can cause it. 
2) Cardiac tamponade
When too much of fluids build up around the heart and put pressure on it, the heart finds it difficult to pump blood properly. This is called cardiac tamponade.

3) Severe left ventricular dysfunction (SLVD)
When the left side of the heart is weak and can't pump blood properly, it causes SLVD. A past cardiac arrest, long-term high BP and more can lead to such a situation. 
4) Arrhythmias
Arrhythmias mean irregular—too slow or fast, or uneven—heartbeats, as the heart's electrical signals are weak. Not all arrhythmias are harmful, but some can lead to a stroke or cardiac arrest. 
5) Aortic dissection
It's a condition in which the aorta's inner layer gets torn. In such a case, blood rushes through the tear, causing the inner and outer layers of the artery to separate, leading to a rupture and severe internal bleeding

6) Acute valvular dysfunction 
When a heart valve suddenly stops functioning, it causes acute valvular dysfunction. It puts strain on the heart and results in poor circulation. 
Manoj Bharathiraja has over 100K search volume on Google Trends in the past 14 hours.