She had just left the hospital, and had so many scheduled doctor’s appointments over the next several weeks that the last thing she wanted to do was going to the emergency department. There were things to do around the house…shopping, cleaning, mail. Friends were coming over. But the chest pressure that had starting after waking up this morning would just not stop.
This 70-year-old woman had been through a lot recently. She had suffered with aortic stenosis for many years. After long talks with her many physicians and surgeon and a carefully considered pro/con list, she had agreed to undergo surgery. She underwent an surgical aortic valve replacement with a bioprosthetic valve. She had planned her surgery thoroughly. She knew what to expect on getting to the hospital, the day of surgery, and what each day after surgery would involve up to her expected discharge on POD #4. Her planning had comforted her, and gave her control of the situation. At least perceived control.
She had been home from the hospital for 3 days, when the chest pressure had started. Unwilling to call it pain or quantify it beyond “its there”, it was ultimately her daughters (with their own lists of worrisome symptoms from the surgeon), that forced her to the ED. She had also experienced some lightheadedness and nausea.
The ECG shows a bradycardia at rate of approximately 36 bpm. There is a right bundle branch block. P-waves are present and occur at regular intervals. There are also non-conducted p waves. The PR interval of the conducted p-waves remains constant and is at the high-end of normal (~200 ms). Most importantly the RR interval of the around the dropped QRS complexes is a multiple of the conducted beats. This is second-degree atrioventricular block, type II (Mobitz). This along with complete heart block (3rd degree), are colloquially called high-degree AV block because of the risk of degenerating.
The ECG does not demonstrate ischemic features (dynamic T waves, T wave inversions, ST segment elevation or depression, QT prolongation). New onset bradycardia and conduction blocks should always prompt you to consider ischemia. In this particular patient acute coronary syndrome would be unlikely. Patients who have planned valvular heart repair, undergo coronary angiography to identify comorbid obstructive atherosclerotic disease. This is so coronary bypass surgery could be done at the same time as the valve surgery. Since she had isolated AVR, we could conclude that her coronary artery disease burden is low significantly reducing, though not eliminating the likelihood of acute plaque rupture.