Transesophageal echocardiography assessment of severe ostial left main coronary stenosis

Delayed-Onset Left Main Coronary Artery Obstruction More than 24 Hours after Balloon-Expandable Transcatheter Aortic Valve Replacement

Coronary obstruction during or after transcatheter aortic valve replacement is a rare and catastrophic sequela that occurs most frequently just after valve implantation. Even rarer is the delayed clinical presentation, in some few patients, of coronary obstruction on the day after self-expandable valve implantation. Here we describe a case of balloon-expandable (not self-expandable) transcatheter aortic valve replacement, followed by partial obstruction of the left main coronary artery on the day after that procedure in a 93-year-old man, despite normal left ventricular contraction just after valve implantation. Visual evaluation of the echocardiogram for left ventricular wall motion was not sufficient, by itself, to achieve early diagnosis of the obstruction. We performed emergency percutaneous coronary intervention. Ninety days after the procedure, the patient was in New York Heart Association functional class I.

Surgical reconstruction of the left main coronary artery with patch-angioplasty

Background

Conventional coronary artery bypass grafting (CABG) has been established as the treatment of choice for left main coronary artery (LMCA) stenosis However, the conventional grafting provides a retrograde perfusion to extensive myocardial area and leads prospectively to competitive flow of the non-occluded coronaries thus consuming the grafts. Surgical reconstruction of the LMCA with patch-angioplasty is an alternative method that eliminates these drawbacks.

Methods

Between February 1997 and July 2007, 37 patients with isolated LMCA stenosis were referred for surgical ostial reconstruction. In 27 patients (73%) surgical angioplasties have been performed. All patients were followed up clinically and with transesophageal echocardiography (TEE) and coronary angiography when required.

Results

In 10 patients (27%) a LMCA stenosis could not be confirmed. There were no early mortality or perioperative myocardial infarctions. The postoperative course was uneventful in all patients. In 25 patients, TEE demonstrated a wide open main stem flow pattern one to six months after reconstruction of the left main coronary artery with one patch mild aneurysmal dilated.

Conclusions

The surgical reconstruction with patch-angioplasty is a safe and effective method for the treatment of proximal and middle LMCA stenosis. Almost one third of the study group had no really LMCA stenosis: antegrade flow pattern remained sustained and the arterial grafts have been spared. In the cases of unclear or suspected LMCA stenosis, cardio-CT can be performed to unmask catheter-induced coronary spasm as the underlying reason for isolated LMCA stenosis.

The hand-carried echocardiographic device as an aid to the physical examination

Physical examination skills have been declining over the past several decades while technology has made diagnostic testing increasingly sophisticated. For patients with cardiovascular disease, the best approach to bedside diagnosis would be one that combines both physical examination and ready access to technology at the time of the patient encounter. Most cardiac testing is not performed at the bedside due to equipment size and time limitations for these tests. Small hand-carried echocardiographic devices are now available for rapid bedside examination. These devices compare well to full-featured systems when used in cardiology outpatient settings and in hospitalized patients who are not critically ill. Compared with physical examination by board certified cardiologists, these devices decrease diagnostic error. Early use of hand-carried echocardiographic devices after physical examination has been demonstrated to impact patient triage and treatment as well as uncover otherwise undetected cardiac disease. The degree of training required for responsible use of these devices is as yet unclear. However, organized training sessions have resulted in modest agreement with standard echocardiography and point-of-care echocardiography performed by expert echocardiographers. It is conceivable that the hand-carried echocardiographic devices will be used in medical school curriculum to enhance medical student education in the future.