Enhanced coronary blood flow velocity during intraaortic balloon counterpulsation in critically ill patients.

OBJECTIVES: The aim of this study was to assess coronary blood flow during intraaortic balloon counterpulsation by direct measurement. BACKGROUND: In a majority of human studies, increased coronary blood flow during intraaortic balloon counterpulsation measured by indirect techniques has not been consistently demonstrated. METHODS: Hemodynamic variables and coronary blood flow velocity (20-MHz Doppler-tipped catheter) data were measured in 19 patients requiring intraaortic balloon pumping for clinical indications (11 patients had acute myocardial infarction [9 with shock], 6 had unstable angina, 1 had acute mitral regurgitation and 1 was at high risk undergoing angioplasty). Hemodynamic data, mean and phasic diastolic flow velocity and velocity-time integrals (computed from digitized waveforms) were analyzed during periods of 1:1 balloon counterpulsation. RESULTS: Intraaortic balloon pumping decreased systolic pressure (6 +/- 10%, p < 0.001) and increased diastolic pressure (80 +/- 30% from baseline, p < 0.001) without changing RR interval. Peak phasic, mean coronary flow velocity and diastolic flow velocity integral were significantly increased (115 +/- 115%, 67 +/- 61%, 103 +/- 81%, respectively, all p < 0.001) during intraaortic balloon pumping. In addition, although a wide splay of data was evident due to operator set variations in balloon inflation and deflation timing, the greater increases in diastolic flow velocity integral (DFVi) occurred in patients with basal systolic pressure < or = 90 mm Hg (% delta DFVi = 102 - 0.1.[unaugmented systolic pressure], SEE = 21.7 mm Hg, r = 0.30, p < 0.001). CONCLUSIONS: Intraaortic balloon pumping unequivocally and significantly augments proximal coronary blood flow velocity, nearly doubling the coronary flow velocity integral in most patients. This mechanism may be a significant means of ischemia relief in hypotensive patients.

Intravenous adenosine: continuous infusion and low dose bolus administration for determination of coronary vasodilator reserve in patients with and without coronary artery disease.

To assess the use of adenosine as an alternative agent for determination of coronary vasodilator reserve, hemodynamics and coronary blood flow velocity were measured at rest and during peak hyperemic responses to continuous intravenous adenosine infusion (50, 100 and 150 micrograms/kg per min for 3 min) and intracoronary papaverine (10 mg) in 34 patients (17 without [group 1] and 17 with [group 2] significant left coronary artery disease), and in 17 patients (11 without and 6 with left coronary artery disease) after low dose (2.5 mg) intravenous bolus injection of adenosine. The maximal adenosine dose did not change mean arterial pressure (-10 +/- 14% and -6 +/- 12% for groups 1 and 2, respectively) but increased the heart rate (15 +/- 18% and 13 +/- 16, respectively). For continuous adenosine infusions, mean coronary flow velocity increased 64 +/- 104%, 122 +/- 94% and 198 +/- 59% and 15 +/- 51%, 110 +/- 95% and 109 +/- 86% in groups 1 and 2, respectively for each of the three doses. Mean coronary flow velocity increased significantly after 100 and 150 micrograms/kg of adenosine and 10 mg of intracoronary papaverine (48 +/- 25, 52 +/- 19 and 54 +/- 21 cm/s, respectively; all p less than 0.05 vs. baseline) and was significantly higher than in group 2 (37 +/- 24, 32 +/- 16, 41 +/- 23 cm/s; all p less than 0.05 vs. group 1). The coronary vasodilator reserve ratio (calculated as the ratio of hyperemic to basal mean flow velocity) for adenosine and papaverine was 2.94 +/- 1.50 and 2.94 +/- 1.00, respectively, in group 1 and was significantly and similarly reduced in group 2 (2.16 +/- 0.81 and 2.38 +/- 0.78, respectively; both p less than 0.05 vs. group 1). Low dose bolus injection of adenosine increased mean velocity equivalently to that after continuous infusion of 100 micrograms/kg, but less than after papaverine. There was a strong correlation between adenosine infusion and papaverine for both mean coronary flow velocity and coronary vasodilator reserve ratio (r2 = 0.871 and 0.325; SEE = 0.068 and 0.189, respectively; both p less than 0.0005). No patient had significant arrhythmias or prolongation of the corrected QT (QTc) interval with adenosine, but papaverine increased the QT (QTc) interval from 445 +/- 44 to 501 +/- 43 ms (p less than 0.001 vs. both maximal adenosine and baseline) and produced nonsustained ventricular tachycardia in one patient.(ABSTRACT TRUNCATED AT 400 WORDS)

Early ambulation after 5 French diagnostic cardiac catheterization: results of a multicenter trial.

Because earlier ambulation and discharge after cardiac catheterization may result in the increased utilization of outpatient facilities, a prospective five center clinical pilot trial assessing the safety and outcome of early ambulation after routine left heart catheterization was performed in 287 patients. Catheterization routines at each clinical center were unchanged throughout the study. After the diagnostic catheterization using 5 French (F), preformed, large lumen catheters and arterial puncture compression (mean 15 min, range 5 to 52), 260 patients were ambulated by a physician at a mean time of 2.6 h (range 1.8 to 3.1) after catheterization. Follow-up examination or a phone call 24 to 72 h later was performed to assess late results. The mean age of the patients was 58 years (range 25 to 91); 166 (58%) were men. Left ventricular ejection fraction was 54 +/- 15%. One hundred twenty-seven patients (44%) received intravenous heparin (1,500 to 5,000 U as an intravenous bolus) and 136 (47%) received aspirin. Major complications included transient ischemic attack (one patient) and ventricular tachycardia requiring cardioversion during ventriculography (two patients). A small hematoma (less than 5.0 cm) after ambulation occurred early (from compression to standing) in 14 patients (5%; 9 received heparin, 8 were taking aspirin) and later (after standing to 72 h) in 9 patients (3%; 2 receiving heparin, 2 taking aspirin). Five patients with a hematoma had studies with a 6F sheath. No patient required surgical intervention for early or late hematoma. Only three patients (1%) needed a 7F or 8F catheter because of suboptimal 5F coronary angiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary hypertension secondary to serum hyperviscosity in a patient with rheumatoid arthritis.

A patient with rheumatoid arthritis who was evaluated for dyspnea of six months' duration is described. Although no primary cardiac or parenchymal lung disease was identified, right heart catheterization revealed marked pulmonary hypertension. The patient was presumed to have pulmonary arteritis. Evaluation of her hyperproteinemia, however, led to the discovery of a polyclonal gammopathy with a marked increase in plasma viscosity. Although the classic clinical findings of the hyperviscosity syndrome were minimal, the patient underwent plasmapheresis, resulting in a marked reduction of pulmonary artery pressures (from 53 +/- 4 mm Hg, mean +/- SD, to 30 +/- 3 mm Hg, p less than 0.05) and pulmonary vascular resistance (from 707 +/- 63 dynes/second/cm5 to 421 +/- 72 dynes/second/cm5, p less than 0.05) concomitant with a return to normal plasma viscosity. Her dyspnea completely resolved. This represents the first successful treatment of pulmonary hypertension by plasmapheresis. Protein evaluation revealed the presence of intermediate complexes of IgG rheumatoid factor. The hyperviscosity syndrome should be considered in the differential diagnosis of pulmonary hypertension in patients with rheumatoid arthritis and other disorders associated with a polyclonal or monoclonal gammopathy. Pulmonary hypertension secondary to the hyperviscosity syndrome is reversible by plasmapheresis. Immunosuppressive therapy that reduces immunoglobulin production may provide a means of long-term treatment.

Rapid identification of the course of anomalous coronary arteries in adults: the "dot and eye" method.

It is often difficult to delineate the true course of anomalous coronary arteries by angiography because it only provides a 2-dimensional view of a complex 3-dimensional structure. The purpose of this study was to confirm morphologically the radiographic appearance of anomalous coronary arteries and to construct a protocol for rapid determination of their true course. Twenty-one adults who had anomalous origin of coronary arteries without other evidence of congenital heart disease were reviewed. Using an anatomically correct model of the heart, solder wire was placed in the pathologically described anomalous positions and radiographed. With this model the pathologically described courses could be easily recognized and separated radiographically. These courses were confirmed in the operating room in 2 patients and a rare anomaly of posterior origin of a coronary artery was also confirmed by autopsy.

Importance of myocardial infarct artery patency on the prevalence of ventricular arrhythmia and late potentials after thrombolysis in acute myocardial infarction.

Sustained infarct artery patency is an important determinant of survival in patients with acute myocardial infarction. We studied 61 patients with acute myocardial infarction who received intravenous recombinant tissue-type plasminogen activator, aspirin or heparin within 6 hours of symptom onset, to determine if infarct artery patency after intravenous thrombolytic therapy influences myocardial electrical stability as measured by the prevalence of spontaneous ventricular ectopy or late potential activity. Infarct artery patency was determined by angiographic evaluation 2.5 +/- 3 days after infarction. Forty-eight patients (79%) had a patent infarct-related artery and 13 (21%) patients had an occluded vessel. The mean number of ventricular premature complexes (VPCs)/hour (p less than 0.01) and the prevalence of late potentials (54 vs 19%; p less than 0.03) were significantly higher in patients with an occluded versus patent-infarct related vessel. Although VPC frequency and late potentials were not influenced by the time to thrombolytic treatment, patients with a patent infarct-related artery had a lower prevalence of late potentials regardless of whether treatment was initiated less than or equal to 2 hours (25% patent vs 50% occluded; p = not significant) or 2 to 6 hours (16% patent vs 55% occluded; p greater than 0.03) after symptom onset. Thus, successful thrombolysis decreases the frequency of ventricular ectopic activity and late potentials in the early postinfarction phase. The reduction in both markers of electrical instability may help explain why the prognosis after successful thrombolysis is improved after acute myocardial infarction.

Predictors of cardiac survival after percutaneous transluminal coronary angioplasty in patients with severe left ventricular dysfunction.

To assess the outcome of percutaneous transluminal coronary angioplasty (PTCA) in patients with severe left ventricular (LV) dysfunction and to determine the predictors of mortality, 73 patients with LV ejection fraction less than or equal to 40% who underwent initial PTCA were analyzed. The majority of patients had prior (greater than 1 week) myocardial infarction (62 patients, 85%). Congestive heart failure and unstable angina were present in 24 (45%) and 49 (67%) patients, respectively. Multivessel coronary artery disease was present in 60 (83%). The LV ejection fraction ranged from 14 to 40% (mean 34%). Intraaortic balloon pump (15%) and percutaneous cardiopulmonary bypass support (4%) was used infrequently. Angiographic success was obtained in 109 of 128 lesions (85%) attempted. Complete revascularization was obtained in 16 of 60 patients with clinical success. Procedure-related mortality was 5% (4 patients). All patients were followed from greater than or equal to 6 to less than or equal to 71 months (average 26). The estimated survival was 79 +/- 5%, 74 +/- 6%, 66 +/- 7% and 57 +/- 8% at 1, 2, 3 and 4 years, respectively. A Cox regression analysis revealed that the presence of congestive heart failure, a lower LV ejection fraction and a higher myocardial jeopardy score for contractile myocardium were independent predictors of survival after PTCA in patients with LV dysfunction. In conclusion, a high-risk subset can be identified among patients with severe LV dysfunction who undergo PTCA.

Effect of abruptly increased intrathoracic pressure on coronary blood flow velocity in patients.

To assess the effects of abruptly increased intrathoracic pressure on coronary blood flow, arterial pressure, heart rate, and intracoronary Doppler blood flow velocity were measured continuously during cough(s) and again during the four phases of the Valsalva maneuver in 14 patients. Coughing significantly increased the systolic pressure (137 +/- 25 to 176 +/- 30 mm Hg), diastolic pressure (72 +/- 10 to 84 +/- 18 mm Hg), and arterial pulse pressure (65 +/- 27 to 92 +/- 35 mm Hg), with no change in heart rate. The mean coronary flow velocity decreased (17 +/- 10 to 14 +/- 12 cm/sec, p less than 0.03). During the Valsalva maneuver, despite marked reduction in the mean arterial pressure during phase III (96 +/- 12 to 68 +/- 14 mm Hg, p less than 0.05), the reduction of coronary blood flow velocity did not achieve statistical significance. These data demonstrate that neither type of abrupt physiologic increase in intrathoracic pressure enhances coronary blood flow. Coughing does not improve coronary perfusion pressures or flow velocity, despite marked increases in arterial diastolic pressure. The Valsalva maneuver, for the most part, does not significantly alter coronary blood flow velocity.

Ventricular arrhythmia due to intracoronary papaverine: analysis of QT intervals and coronary vasodilatory reserve.

Intracoronary papaverine commonly produces striking QT interval prolongation with rare but serious ventricular dysrhythmias reported. Because of 3 cases of severe papaverine-induced dysrhythmia in our laboratory, QT intervals and hemodynamic and intracoronary velocity data collected during intracoronary papaverine administration were retrospectively reviewed in 34 patients; 20 patients with angiographically normal coronary arteries (group 1) and 14 patients (group 2) before and (group 2) after single-vessel left coronary angioplasty. QT intervals increased from 394 +/- 44 to 464 +/- 73 msec, 414 +/- 47 to 504 +/- 95 msec, and 410 +/- 41 to 486 +/- 75 msec for groups 1 and 2 before and after angioplasty, respectively (all P less than 0.01). There was no correlation with hemodynamic, electrocardiographic, or coronary vasodilatory reserve responses and change in QTc interval. In the 3 index patients having significant papaverine-related arrhythmias, a baseline QT interval was prolonged (after prior papaverine exposure) in only 1 in association with torsade de pointes. These data indicate that QT interval prolongation after papaverine is a common occurrence, but that the production of ventricular dysrhythmia is probably idiosynchratic in origin. In view of these findings, we recommend that appropriate antiarrhythmic preparations be in place for patients receiving intracoronary papaverine.

Attenuation of pulsus alternans during coronary angiography.

Following coronary angiography in a patient with cardiomyopathy and pulsus alternans, we observed a transient but marked attenuation of the alternation in pulse pressure associated with an elevation in pulmonary artery pressure. Attenuation of pulsus alternans has been rarely reported and may represent further deterioration of ventricular function.

Diagnostic changes in plasma creatine kinase isoforms early after the onset of acute myocardial infarction.

Conventional plasma isoenzyme and enzyme values usually are normal during the first few hours of acute myocardial infarction. Thus definitive diagnosis may be delayed. We have shown recently that infarction in dogs can be detected within 1 hr after coronary occlusion by analysis of relative activities of MM creatine kinase (CK) isoforms in plasma. Isoforms of MM CK evolve through posttranslational modifications in plasma of the form released from tissue (MMA) to MMB and MMC. In this study we quantified changes in isoform profiles in the first available plasma samples from patients with evolving myocardial infarction, from patients with angina, and from normal subjects. In the 26 control subjects, the ratio of MMA to MMC was 1.09 +/- 0.4 (SE) (range 0.31 to 3.1; upper limit of normal [defined as the mean plus 2 SD] 2.5). In the seven control patients with coronary artery disease, the ratio of MMA to MMC was 1.3 +/- 0.3 with a range of 0.5 to 2.5. In contrast, among the 28 patients with acute myocardial infarction, the ratio of MMA to MMC in the first available plasma sample averaged 14.6 +/- 4.5 (p less than .01 compared with both control groups). First available samples were obtained 3.9 +/- 0.4 hr after the onset of pain. In 24 of 28 patients (86%) the ratio of MMA to MMC was greater than 2.5.(ABSTRACT TRUNCATED AT 250 WORDS)

Improved method for transcatheter retrieval of intracoronary detached angioplasty guidewire segments.

A transcatheter technique using a probing catheter and 0.014 wire to form a loop snare was used percutaneously to safely retrieve segments of retained guidewire fragments in mid- and distal coronary arteries in three patients.

Conversion of MM creatine kinase isoforms in human plasma by carboxypeptidase N.

This study was undertaken to identify the carboxypeptidase(s) (CPase) in plasma mediating sequential conversion of the tissue isoform of the MM isoenzyme of creatine kinase (MM3 CK) to MM2 and MM1 isoforms and to elucidate relationships between CPase activity measured in plasma and observed rates of isoform conversion in vitro. Purified MM3 was incubated at 37 degrees C in plasma from normal subjects and patients with acute myocardial infarction. Isoforms were quantified by chromatofocusing. Preincubation with antiserum to CPase N prevented conversion of added MM3 to MM2 and MM1. Isoform conversion rates in the absence of antibody were proportional to plasma CPase N activity assayed spectrophotometrically by hydrolysis of furylacryloyl-L-alanyl-L-lysine substrate (r = 0.89, n = 8). Plasma CPase N activity varied by nearly 300% among individuals, but average activity was similar in samples from normal subjects (267 +/- 45 [SD] U/L, n = 18), those from outpatients with angina (289 +/- 43 U/L, n = 9), and those obtained at hospital admission from patients with acute infarction (Q wave: 279 +/- 70 U/L, n = 16; non-Q wave: 272 +/- 61 U/L, n = 14) or unstable angina (280 +/- 71 U/L, n = 11). In patients with Q wave infarction, CPase N activity increased by 43% +/- 25% between 48 hours and 72 hours (P less than 0.005 compared with admission) with a concomitant change in the rate of conversion of isoforms. Thus, the rate of conversion of isoforms in individual subjects can be estimated by assay of CPase N activity in plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of coronary arteriography in the preoperative management of patients undergoing urgent repair of the thoracic aorta.

Noninvasive innovations have advanced the timing and precision of diagnosis of acute dissection or enlarging aortic aneurysm. However, the need to perform coronary arteriography prior to surgical repair in these patients remains a question for many clinicians. This retrospective 10-year (1978 to 1988) review examined data of 54 patients undergoing urgent surgical repair of thoracic aortic tear, aneurysm, or dissection in our institution. Results of coronary arteriography and clinical variables (history of coronary artery disease, electrocardiographic abnormalities, surgical procedures, and in-hospital mortality) were tabulated. Twenty-seven patients had type A aortic dissection and 27 patients had type B. Twenty-four patients had aortic dissection or tear (type A or B) due to motor vehicle trauma. In patients with type A, a history and/or electrocardiogram suggestive of coronary artery disease was present in 16, in whom cardiac catheterization was performed in five. None required coronary bypass surgery or died. In the 11 patients with no clinical history of coronary artery disease or electrocardiographic abnormalities, six had cardiac catheterization, none had coronary artery disease, two had coronary reimplantation, and six died. Only 1 of the 27 patients with type A dissection had a perioperative myocardial infarction (a patient with a clinical history of coronary artery disease who did not undergo cardiac catheterization). In patients undergoing type B aortic repair, 10 had a clinical history or electrocardiogram consistent with coronary artery disease but only one underwent cardiac catheterization and subsequent coronary artery bypass graft surgery for coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of high (sodium meglumine diatrizoate, Renografin-76) and low osmolar (sodium meglumine ioxaglate, Hexabrix) radiographic contrast media on diastolic function during left ventriculography in patients.

Although a majority of studies indicate superior hemodynamic and clinical profiles of low osmolar compared with high osmolar contrast media, the effect of these agents on diastolic left ventricular function has not been examined. We prospectively examined hemodynamic, electrocardiographic, and echocardiographic indices of left ventricular function in patients undergoing contrast ventriculography with a high osmolar, ionic, monomeric contrast, diatrizoate (Renografin-76) compared with a low osmolar, ionic, dimeric contrast, ioxaglate (Hexabrix). Thirty patients were randomized to each group. There were no clinical differences between the two groups. The decrease in systemic pressures was significantly greater with diatrizoate after left ventriculography (-38.5 +/- 3.5 versus -18.2 +/- 2.3, p less than 0.001) and selective left coronary angiography (-29.5 +/- 2.4 versus -17.4 +/- 2.6, p less than 0.001). In addition, left ventricular end-diastolic pressure increased significantly more with diatrizoate (7.3 +/- 0.9 versus 2.7 +/- 0.8 mm Hg for ioxaglate, p less than 0.001). QT interval prolongation occurred in both patient groups. Diatrizoate decreased systemic vascular resistance, and increased cardiac output and left ventricular ejection fraction more than ioxaglate, while simultaneously increasing left ventricular end-diastolic volume and altering the peak atrial filling velocity. Negative dp/dt (p less than 0.05), but not Tau, computed by the logarithmic or derivative methods, was reduced by diatrizoate. These data indicate that significant alteration of diastolic filling patterns occurs with high osmolar compared with low osmolar contrast agents. Although the clinical significance of this observation is currently unknown, these data further support the reported hemodynamic superiority of the low osmolar, dimeric contrast agent ioxaglate during contrast angiography.

Preliminary experience with 5 and 6 French diagnostic catheters as guiding catheters for coronary angioplasty.

With the reduction in profile of balloon dilation catheters, until recently, it has been the internal dimensions and performance of the guiding catheter that has mandated the use of 7, 8 or 9 French (F) systems for the performance of percutaneous transluminal coronary angioplasty (PTCA). A new 5F catheter design (Sherwood Medical Co., St. Louis, MO) provided a large inner lumen (0.4") permitting use of 0.20-0.22" fixed-wire PTCA balloon catheters with good coronary visualization. Potential advantages include reduced coronary artery ostial trauma and catheter induced damping and enhanced patient comfort. We report our initial experience in 14 patients undergoing PTCA with a 5 and 6F guide/fixed-wire system. Mean age was 63 +/- 10 (43-78 years). PTCA indications: Cardiogenic shock (1), post-myocardial infarction angina pectoris (2), grade III angina (5) and unstable angina pectoris (6). Vessel attempted: Left anterior descending (3), circumflex (4), obtuse marginal (2), diagonal (1), right coronary artery (3), and internal thoracic artery (1). Twelve patients had femoral approach; two brachial approach. The USCI Probe (USCI Division, Billerica, MA) was used in 8 lesions and SCIMED ACE (SCIMED Life Systems, Maplegrove, MN) catheter in 7 lesions. Successful 5 or 6F guide/fixed-wire dilations reduced the stenosis (77 +/- 14 to 37 +/- 30%) and were successfully performed in 79% (11/14). One 5F patient required 8F guiding catheter and was dilated with 2.0 fixed-wire balloon. A second failed 5F PTCA could not be dilated with any larger conventional system. A third total occlusion could not be crossed with a guidewire or fixed wire balloon. No patient had a complication.(ABSTRACT TRUNCATED AT 250 WORDS)