6 min readUpdated: Sep 9, 2026 04:57 PM IST
The death of 65-year-old Pune runner Sanjay Kadam during the Satara Hill Half Marathon has raised an unsettling question: How can someone who is apparently fit enough to run 17 kilometres suddenly suffer a cardiac arrest, be revived and undergo angioplasty to open a blocked artery, and then suffer another cardiac arrest hours later?
The answer lies in understanding what happens to the heart after a major coronary blockage. Kadam, a retired scientist from the Centre for Development of Advanced Computing (C-DAC), was an experienced and enthusiastic runner. He had hypertension but trained regularly. He was participating in the Satara Hill Half Marathon for the first time and had completed about 17 km of the 21.1-km course when he collapsed. A cardiologist participating in the race, Dr Riyaz Mujawar, immediately began CPR (cardiopulmonary resuscitation). Kadam was taken to hospital, where angiography reportedly showed a blockage in a major coronary artery. Doctors performed angioplasty. He was initially stabilised, but later suffered another major cardiac arrest and died.
“The first 24 hours after angioplasty are particularly important because opening a blocked artery does not immediately mean the heart has recovered. If the heart has been deprived of oxygen during a heart attack or cardiac arrest, some of the heart muscle may already be injured or temporarily weakened, and it can remain electrically unstable even after blood flow is restored. This can trigger dangerous abnormal heart rhythms and, in some cases, another cardiac arrest. This is why patients who undergo angioplasty after a major cardiac event are kept under close observation,” says Dr Ranjan Shetty, lead cardiologist and medical director, Sparsh Hospital, Bengaluru. He explains the science to The Indian Express
Heart attack and cardiac arrest
A heart attack is primarily a plumbing problem. Blood flow through one of the coronary arteries becomes severely restricted or blocked, depriving part of the heart muscle of oxygen.
A cardiac arrest is an electrical problem. The heart’s electrical system becomes so unstable that the heart can no longer pump blood effectively. The person loses consciousness, stops having an effective pulse and can die within minutes without CPR and defibrillation.
The two can occur together. A blocked coronary artery can damage heart muscle and destabilise the heart’s electrical system. That can trigger a dangerous rhythm such as ventricular fibrillation, causing cardiac arrest.
Why did his hypertension matter?
Hypertension does not mean that someone cannot exercise or run. In fact, regular exercise is one of the most important lifestyle measures for cardiovascular health. But years of high blood pressure can silently damage the cardiovascular system. Persistent hypertension places additional stress on the artery walls and makes them more prone to plaque deposition, which is an important risk factor for coronary artery disease.
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Besides, someone may have excellent endurance and still have a significant narrowing or blockage in a coronary artery. In Kadam’s case, doctors found a major coronary blockage after he collapsed.
Extreme endurance exercise places considerable demand on the cardiovascular system, particularly when someone is exercising at high intensity or beyond what they are accustomed to. The heart is working harder for an extended period. Heart rate and blood pressure rise, and the heart requires more oxygen. If a coronary artery is significantly narrowed or blocked, there may be a point at which the heart’s oxygen requirement exceeds the supply available through the coronary circulation.
The American Heart Association notes that the risk of acute cardiovascular events can rise during extreme endurance exercise, particularly in people who are inadequately trained or have previously undetected heart disease. That is one reason exertional symptoms should never be dismissed simply because someone is otherwise fit.
Why can the heart arrest again after angioplasty?
A stent or angioplasty can restore blood flow through a blocked coronary artery. But opening the artery does not instantly make an injured heart completely normal. After a major coronary event, several problems may persist. The heart muscle may already have been injured. Even after blood flow is restored, the heart may remain weak or electrically unstable, a risk factor for cardiac arrest.
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Finding and treating one blocked artery is important, but there could have been unstable blockages in other heart vessels. The clinical team therefore has to assess not only the blockage that has been opened but also the overall condition of the heart, its pumping function and its electrical stability.
Cardiac arrest itself is a massive physiological crisis. Even after circulation is restored — what doctors call return of spontaneous circulation, or ROSC — the patient remains critically ill. This is why surviving the first cardiac arrest is not necessarily the end of the emergency.
What warning signs should runners take seriously?
Chest pain or pressure is the obvious warning sign, but heart problems do not always announce themselves dramatically. Account for chest tightness, breathlessness, sudden exhaustion, dizziness or light-headedness, fainting or near-fainting, an unusually rapid or irregular heartbeat, pain or discomfort spreading to the arm, shoulder, back, neck or jaw and a sudden and unexplained decline in exercise capacity.
For someone with hypertension — particularly as age increases — the sensible approach is to keep blood pressure controlled, have cardiovascular risk factors reviewed and discuss any new symptoms or major increase in exercise intensity with a doctor. Someone preparing for a half marathon after a period of relatively lower activity should also build training progressively rather than suddenly increasing distance and intensity.
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Rapid CPR, immediate medical attention, defibrillation when indicated and rapid treatment of the underlying coronary problem can make the difference between life and death.
