Kenneth B. Johnson

Routine femoral head fluoroscopy to reduce complications in coronary catheterization

We tested whether routine preprocedure fluoroscopy of the femoral head would improve sheath placement or reduce the incidence of groin complications. Patients were randomized to receive either fluoroscopy or “blind” sheath placement using palpation alone. The location of the femoral sheath was established by femoral artery angiography. Sheath placement in relation to the femoral head, arterial location, and complication rates were compared. Placement was considered “ideal” if the sheath was in the common femoral artery and in the top or middle third of the femoral head. A total of 256 patients were enrolled. There was no difference in average age, body mass index (BMI), or rate of anticoagulation between the groups. There was no major bleeding in either group. The overall risk of minor bleeding was not statistically different. The treatment group showed higher “ideal” placement relative to the femoral head. In patients who had a BMI ≥30 kg/m2, the difference between the groups was statistically significant (treatment 69% vs control 50%). In conclusion, routine femoral fluoroscopy prior to sheath placement in coronary angiography and angioplasty did not significantly alter bleeding or complication rates but did increase the likelihood of ideal placement, especially in obese patients.

Computed tomographic coronary angiography: experience at Baylor University Medical Center/Baylor Jack and Jane Hamilton Heart and Vascular Hospital

Noninvasive cardiac computed tomographic imaging using multislice or electron beam technology has been shown to be highly specific and sensitive in diagnosing coronary heart disease. It is about a fifth of the cost of coronary angiography and is particularly well suited for evaluating patients with a low or low to moderate probability of having obstructive coronary atherosclerosis. In addition, it offers more information than calcium scoring: because of the intravenous contrast used, it temporarily increases the density of the lumen and allows differentiation of soft plaque from calcified plaque. The Baylor Hamilton Heart and Vascular Hospital now uses this modality to define coronary atherosclerosis in patients who would otherwise have needed invasive coronary angiography; several research protocols with the technique are also under way. Baylor has recently upgraded to the 64-slice scanner. It is expected that computed tomographic coronary angiography will replace a significant percentage of invasive cardiac catheterizations.

Superiority of Computed Tomography Coronary Angiography Over Calcium Scoring to Accurately Evaluate Atherosclerotic Disease in a 35-Year-Old Man

A 35-year-old man with juvenile onset diabetes mellitus presented with exertion-associated chest pain. His risk factors also included smoking, hyperlipidemia, and strong family history. As part of a research protocol, he received a calcium score as well as multislice (computed tomography [CT]) coronary angiography using a new, 16-slice scanner (Lightspeed 16, GE Systems). There was no detectable epicardial coronary calcium (Figure 1). However, his noninvasive coronary angiogram demonstrated a high-grade stenosis in his mid-left anterior descending artery (LAD) (Figure 2 and Figure 3⇓). Additionally, there was a significant amount of plaque burden noted in the proximal LAD …

Critical left main coronary artery stenosis diagnosed by computed tomographic coronary angiography.

A 60-year-old man with previous cerebrovascular accident, hypercholesterolemia, and tobacco use presented with a several-month history of worsening exertional dyspnea. Immediate catheterization was considered unsafe, as the patient was taking warfarin (international normalized ratio, 2.9), and nonemergent, as the patients symptoms were relatively stable. Warfarin was stopped, and multislice computed tomographic coronary angiography (CTCA) was performed (Lightspeed 16, GE Systems) after obtaining appropriate consent. CTCA demonstrated a high-grade narrowing at the ostium of the left main coronary artery (Figure ​(Figure1,1, arrowheads). The ostium of the left main coronary artery had a tapered appearance and a large plaque in its ostial and proximal portions (Figure ​(Figure1b,1b, black arrow). A large amount of plaque was seen in all coronary distributions. Figure 1 Computed tomographic coronary angiogram demonstrating critical left main coronary artery stenosis. (a, b) The multiplanar reformat views clearly demonstrate a high-grade stenosis (arrowheads). (b) The plaque contains both soft and calcified components ... Cardiac catheterization was performed using a 4F system in an attempt to avoid excessive trauma to the artery. In addition, an intraaortic balloon pump and console were positioned inside the cardiac catheterization suite. Invasive coronary angiography demonstrated a critical stenosis of the left main coronary artery (Figure ​(Figure2,2, arrowhead), with pressure damping upon engagement of the 4F Judkins left catheter. The intraaortic balloon was placed, and the patient went on to have successful 5-vessel coronary artery bypass grafting that afternoon. Figure 2 Conventional invasive angiography confirmed the critical stenosis (arrowhead). CTCA allowed us to “preview” the coronary anatomy in a patient whose invasive catheterization was delayed due to anticoagulation. Demonstration of the critical stenosis prior to the catheterization allowed us to change the timing of the catheterization (which was originally planned for the next week) as well as the strategy. Normally, 6F catheters would have been used, which might have been more traumatic given the severity of the ostial left main artery stenosis. In addition, foreknowledge of the severity of the stenosis allowed us to plan for likely intraaortic balloon insertion.

Balloon rupture during stent implantation: A novel technique of salvage with a new manual power injector

Pinhole leak or rupture of a stent delivery balloon is a well‐recognized technical problem encountered in vascular interventions. This event leads to inadequate stent expansion. These stents cannot be fully deployed with the same balloon and frequently the balloon cannot be retrieved without dislodging the stent. We describe a technique for successful stent deployment in such situations using the Oz Power Syringe, a new manual power injector. Cathet. Cardiovasc. Intervent. 48:74–77, 1999.

A New Type of Handheld Power Syringe for Cardiovascular Angiography

• diagnostic coronary angiography using 5F and 6F catheters, particularly in patients with high coronary resistance or flows (e.g., patients with hypertension, left ventricular hypertrophy, aortic regurgitation); • angiography of the iliac and femoral vessels; • aortography; • ventriculography; • percutaneous transluminal coronary angiography using 6F or 7F guiding catheters; and • coronary interventions using bulky devices (e.g., rotational atherectomy with large burrs, directional atherectomy, excimer laser angioplasty, and others).