It says more about poor medical oversight and clinical scrutiny by the FAA.
61 years old, a family history of strokes and becoming increasingly obese - doesn't take a rocket scientist to work out what might happen, especially if his BP is high as well - and he had been on medication, presumably to lower his BP.
An ECG might tell you if the heart is damaged, diseased or abnormal but won't tell you if you are prone to strokes.