Coronary atherectomy versus angioplasty: the CAVA Study.

Directional coronary atherectomy was developed with the hope that it would lower the risk of acute closure and restenosis by leaving a larger smoother lumen and fewer dissections than angioplasty. To evaluate this hypothesis, we compared the clinical and angiographic results of directional coronary atherectomy with those of percutaneous transluminal coronary angioplasty in well-matched groups. We studied 126 consecutive atherectomies and 127 angioplasties performed on similar lesions. Procedural results were evaluated with regard to dissections, complications, acute closure, and residual stenosis. Each patient's clinical course was followed, and each patient was contacted at 6 months for evaluation of recurrent angina, need for repeat catheterization, and angiographic rate of restenosis. Baseline clinical and angiographic characteristics of the two groups were well matched and met the criteria established as being appropriate for atherectomy. The angiographic success rate was 98% after angioplasty and 99% after atherectomy. There were fewer dissections after atherectomy (13%) compared with the number after angioplasty (22%; p = 0.03). Residual stenosis was 8.3 +/- 9% after atherectomy compared with 15 +/- 12% after angioplasty (p = 0.0001). However, there were more complications after atherectomy (p = 0.03). There was no significant difference between the two groups in the recurrence rate of angina or in the angiographic restenosis rate at 6 months. It was concluded that when lesion characteristics and vessel size are appropriate for atherectomy, the procedural success rate of either atherectomy or angioplasty is extremely high. Although atherectomy leads to a larger residual lumen and fewer dissections, the complication rate after atherectomy is higher than that after angioplasty. There is a trend toward more occlusions after atherectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary angiography with 5 French diagnostic catheters may miss an ostial left main stenosis.

Critical ostial left main disease may lead rapidly to sudden death and is, therefore, of paramount importance to diagnose. While the number of cardiac catheterizations is increasing, government and third party reimbursement sources are imposing pressure to perform more studies in an outpatient setting, as the economic resources for medical procedures are shrinking. Outpatient cardiac catheterization requires the patient to ambulate within several hours after the procedure. In order to allow patients to safely ambulate early after their procedures, 5 French catheters are often used (whether the femoral or brachial approach is used) rather than the standard 7 French catheters. We describe a patient with an ostial left main stenosis that was not visualized when coronary arteriography was performed using a diagnostic 5 French catheter. Selective intubation of the left main coronary artery was easily achieved without damping of the pressure tracing. Selective coronary angiography did not demonstrate the ostial stenosis, and there appeared to be a normal amount of contrast refluxing into the aortic root. When the patient returned for an angioplasty and a guiding angiogram was performed with an 8 French catheter, an ostial stenosis was evident with coronary angiography.

A cyclic breathing pattern in patients with poor left ventricular function and compensated heart failure: a mild form of Cheyne-Stokes respiration?

OBJECTIVES: This study was designed to evaluate the breathing patterns of patients with poor left ventricular systolic function and compensated heart failure. BACKGROUND: Cheyne-Stokes respiration is often found in patients with severe decompensated heart failure. Breathing patterns of patients with clinically moderate congestive heart failure have not been well described. METHODS: Tidal volume, oxygen consumption, carbon dioxide production, respiratory rate, minute ventilation and partial pressure of end-tidal oxygen and of end-tidal carbon dioxide were measured in 36 consecutive patients with an ejection fraction < 40% and compensated congestive heart failure. Measurements were made with a computerized expiratory gas analyzer. RESULTS: Nine of the 36 patients demonstrated a cyclic breathing pattern, with a cycle length of 130 +/- 82 s. At the peak of the cycle, minute ventilation was 16.7 +/- 2.9 liters/min, tidal volume was 582 +/- 130 ml, end-tidal carbon dioxide was 25 +/- 2.7 mm Hg and end-tidal oxygen was 121 +/- 4.9 mm Hg. At the nadir of the cycle, minute ventilation was 9.5 +/- 2.1 liters/min, tidal volume was 372 +/- 120 ml, end-tidal carbon dioxide was 35 mm Hg +/- 2.1 and end-tidal oxygen was 101 +/- 3.9 mm Hg. Respiratory rate was 27 +/- 5.9 breaths/min at peak and 24 +/- 5.1 breaths/min at nadir (p = NS). Patients with a cyclic respiratory pattern had a significantly lower ejection fraction (15 +/- 5%) compared with patients without cyclic respirations (26 +/- 8%; p < 0.001). There was no difference in the origin of heart failure, clinical status or exercise performance between these two groups. CONCLUSIONS: A cyclic respiratory pattern occurs commonly in patients with mild to moderate heart failure. It is related to poor left ventricular systolic function and not related to clinical status or etiology of heart failure. The cyclic respiratory pattern found commonly in patients with compensated heart failure and very poor ventricular function (ejection fraction < 25%) consists of a variation in tidal volume only. Respiratory rate is relatively constant and true apnea does not occur.

Early postoperative occlusion of a left internal mammary artery bypass graft with subsequent restoration of patency.

Total occlusion of a left internal mammary artery (LIMA) bypass graft is a rare complication, and reversal of a documented occlusion has not been reported. This is a case of an early postoperative occlusion of a LIMA graft that was found to be patent 4 months later. A patient with three vessel disease (including a moderate lesion in the proximal left anterior descending artery and a severe lesion in its mid-portion) underwent coronary artery bypass grafting with a LIMA to the mid-left anterior descending artery (LAD) and saphenous vein grafts to the right coronary and left circumflex arteries. Coronary angiography 3 months after surgery revealed a totally occluded internal mammary artery and saphenous vein grafts. The patient then underwent a successful angioplasty of the more distal lesion in the LAD. She subsequently returned with recurrent angina. Repeat coronary angiography revealed rapid progression of the disease in the proximal LAD with the more distal angioplasty site being widely patent. Selective arteriography of the internal mammary artery at that time revealed a patent vessel. Thus, the internal mammary graft is a physiologically active conduit that is dependent on flow dynamics. Competitive flow through the nonobstructive native LAD in combination with impedance of flow through the internal mammary artery due to a severe lesion in the LAD distal to the anastomosis led to a functionally occluded LIMA. When the obstruction in the proximal LAD progressed and the distal obstruction was successfully angioplastied, the flow dynamics in the internal mammary improved, allowing for its dilatation and restoration of patency.(ABSTRACT TRUNCATED AT 250 WORDS)

New treatment strategies for cardiogenic shock in acute MI. Management options depend on the availability of a cath lab.

Aggressive treatment strategies that include early revascularization may significantly improve survival from acute MI complicated by cardiogenic shock. Symptoms of impending cardiogenic shock include tachycardia, cool extremities, pallor, cyanosis, and a normal or low blood pressure. When possible, the right and left sides of the heart are catheterized immediately. For patients who need to be transferred to a hospital with a catheterization laboratory, use temporary support measures--intubation, administration of positive inotropic agents, and placement of an intra-aortic balloon pump. Coronary angiography can reveal whether direct PTCA or bypass surgery is appropriate. Thrombolysis is limited to patients for whom transfer is delayed and those in whom cardiogenic shock is ruled out.

Symptomatic angina secondary to coronary-subclavian steal syndrome treated successfully by percutaneous transluminal angioplasty of the subclavian artery.

Subclavian artery stenosis causing severely symptomatic angina in a patient with a previous left internal mammary artery bypass to the left anterior descending artery was treated successfully with percutaneous transluminal angioplasty. Baseline arteriography clearly revealed subclavian and coronary steal by evidence of competitive flow of nonopacified blood from the left vertebral artery. Although there was a difference of only 15 mm Hg between the right and left brachial arteries, there was a palpable difference in the upstroke of these pulses. The stenosis in the subclavian artery was successfully dilated with percutaneous transluminal angioplasty. Angiographic evidence of subclavian steal resolved following balloon dilatation, and the patient's angina was completely resolved.

Two hugging balloons at high pressures successfully dilate a lesion refractory to routine coronary angioplasty.

A small portion of lesions are refractory to coronary angioplasty even when very high pressures are used. This leads to a failed angioplasty and emergent bypass surgery. We successfully attempted the technique of hugging balloons or two polyethelene terephthalate (PET) balloons inflated simultaneously side by side which successfully dilated a lesion which would not dilate using standard techniques. This technique successfully dilated the lesion as the geometry of two balloons inflated side by side is different from one balloon. Two balloons inflated side by side consists of two outer semi-circles and a central trapezoidal square area. This altered geometric configuration may be important in successfully dilating a lesion refractory to standard dilating techniques. Higher pressures can be attained with smaller balloons as the burst pressure is higher in smaller balloons compared to larger balloons.

Exercise-induced ventricular tachycardia in association with a myocardial bridge.

Sustained ventricular tachycardia induced by exercise is uncommon. This is a report of a patient who has a positive exercise test at a high level of exercise. The electrocardiogram has classic ischemic ST depressions. Following the appearance of these ST depressions, the patient developed ventricular tachycardia at a rapid rate. Workup that included an echocardiogram and cardiac catheterization revealed myocardial bridging of the left anterior descending artery as the only structural abnormality. Electrophysiologic studies revealed the patient to have ventricular tachycardia only with isoproterenol (Isuprel) infusion.

Severe haemolytic anaemia after replacement of the mitral valve by a St Jude medical prosthesis.

Severe haemolytic anaemia developed in a 33 year old patient after the mitral valve was replaced with a St Jude medical prosthesis. This was the patient's third thoracotomy. She had already had a mitral commissurotomy and a mitral valve bioprosthesis. The patient had an E+ antibody to red blood cells as well as a paraprosthetic leak. The haemolysis became less severe once the population of E+ red cells was completely haemolysed. However, the patient continued to require transfusions to remain out of heart failure. Once the valve was replaced, the haemolysis subsided. Fulminant haemolysis after mitral valve replacement is rare. When it does occur, a paraprosthetic leak should be suspected. Other causes of haemolysis, however, must also be considered and these may contribute to the severity of haemolysis.

Systemic and regional hemodynamic effects of captopril and milrinone administered alone and concomitantly in patients with heart failure.

The effects of milrinone and captopril on ventricular performance, renal blood flow, and femoral vein oxygen content were compared in 11 patients with severe chronic heart failure. The increase in stroke volume index was greater with milrinone than with captopril (28 +/- 7 vs 24 +/- 7 ml/m2; p less than .05), while pulmonary capillary wedge pressures fell similarly (19 +/- 10 vs 21 +/- 7 mm Hg). Mean systemic arterial pressure decreased significantly from 84 +/- 10 to 73 +/- 11 mm Hg (p less than .05) with captopril but did not with milrinone. Neither drug changed heart rate significantly. Although milrinone produced a greater improvement in ventricular performance than captopril, renal blood flow increased similarly with both drugs from 289 +/- 78 to 417 +/- 111 ml/min (p less than .05) and from 278 +/- 77 to 441 +/- 115 ml/min (p less than .05), respectively. Femoral vein oxygen content was increased by milrinone from 7.9 +/- 2.6 to 9.8 +/- 3.0 ml/100 ml (p less than .05) and was not changed by captopril. In seven additional patients, intravenous milrinone, administered at the peak effect of captopril, further augmented stroke volume index from 24 +/- 6 to 32 +/- 6 ml/m2 (p less than .05) and tended to reduce pulmonary capillary wedge pressure further from 20 +/- 8 to 18 +/- 9 mm Hg (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)