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Evaluation of cardiac function during periods of stress is of key importance for the perioperative setting. Non-invasive hemodynamic monitors provide markers of cardiac function. This pilot study sought to evaluate the ability of a non-invasive hemodynamic monitor to detect cardiac stress during formal stress echocardiography testing. The primary goal was to compare the change in hemodynamic values during the pre/during/post phases of stress echocardiography testing in patients who had results negative versus positive for myocardial ischemia. Adult patients scheduled for outpatient cardiac stress testing were screened. Only patients scheduled for stress-echocardiography testing were consented. Patients with history of arrhythmias were excluded. During the testing, patients wore a cuff-based hemodynamic sensor (Nexfin system, Edwards Lifesciences). Data from the hemodynamic sensor were compared to the findings of the stress study. A total of 37 patients were enrolled, with 31 patients included for analysis. Five patients had stress studies positive for coronary ischemia. Comparison of the hemodynamic variables between patients who had a positive stress study versus negative showed a significant reduction in the percentage change in dP/dt and stroke volume from baseline (p

The American Society of Echocardiography (ASE) recognizes that cardiac sonographers are frequently multiskilled and multicredentialed. It is the position of the ASE that, above all, persons who perform cardiac ultrasonography should be fully trained and credentialed in cardiac sonography. If a person is multiskilled (practices another health-related discipline), he or she should be appropriately trained and credentialed in that discipline as well. Possession of multiple credentials provides some evidence that the person has met specific minimum competencies in those areas.This position supports effective, efficient, and high-quality patient care.

Echocardiography is an invaluable diagnostic tool for the evaluation of cardiac form and function. Evaluation of the cardiac form and function requires highly skilled acquisition given that the technique of performing the examination has become increasingly sophisticated. Although several publications exist relating to the role and training of cardiac sonographers, none of these articulate clearly and concisely minimum qualifications for cardiac sonographers. In light of the advances in cardiovascular ultrasound imaging, which have placed growing educational and professional demands on cardiac sonographers, and the fundamental vision of the American Society of Echocardiography (ASE) as being an organization that strives for excellence and stands for quality, ASE believes that such a statement is necessary. The ASE believes that there are 3 primary elements involved in assuring the competence of a cardiac sonographer

To define the clinical utility of the color Doppler proximal isovelocity surface area (PISA) method for estimating regurgitant stroke volume (SV), 160 regurgitant lesions were evaluated in 104 patients with mitral (MR), aortic (AR), and tricuspid (TR) regurgitation. Regurgitant SV by PISA was calculated as 2 pi R2 x V x (time-velocity integral/peak flow velocity), where R is the radius corresponding to the first blue-red interface velocity of the maximal PISA during the cardiac cycle. The time-velocity integral and peak flow velocity from the continuous-wave Doppler recording of the regurgitant jet were used to correct PISA for phasic variations in regurgitant flow. Fifteen lesions were excluded because of difficulty in tracing the continuous-wave Doppler regurgitant curve. Among 145 remaining regurgitant lesions, PISA was measurable in 50 (78%) of 64 cases of MR and 24 (69%) of 35 cases of TR but in only 12 (26%) of 46 cases of AR (p0.001). Regurgitant SV by PISA correlated modestly well with jet area/atrial area in all atrioventricular valve lesions (MR: r = 0.55; TR: r = 0.65; p0.001). However, the correlation improved if only central jets were considered (MR: r = 0.70; TR; r = 0.75; p0.001). These findings are not unexpected because jet area/atrial area underestimates the true severity of regurgitation in cases of eccentric (wall-impinging) jets. PISA was detected in all severe cases of regurgitation but in only 64% of cases of mild MR, 45% of cases of mild TR, and 6% of cases of mild AR (p0.01). The color Doppler PISA method is clinically useful in estimating regurgitant SV in MR and TR, including mild cases, but is less useful in AR.

Whether acute doses of cocaine can induce left ventricular (LV) regional wall motion abnormalities in animals with otherwise normal coronary arteries is unknown. We studied rabbits receiving constant cocaine infusions (group I: 0.025 to 1.5 mg/kg/min, n = 10), multiple cocaine boluses (group II: 3-5 mg/kg each bolus, n = 10), or saline (group III; n = 8). In group I rabbits, short-axis LV area and diameter increased by 15% to 40% at 60 minutes compared to baseline and to controls (p0.01), but percentage of global area fractional shortening was unchanged. Eight rabbits in each of groups I and II, but no controls, developed LV regional wall motion abnormalities as detected by echocardiography: 15 (7 hypokinesis and 8 akinesis or dyskinesis) in the anteroseptal and 2 (hypokinesis) in the posterior LV wall. Among rabbits showing LV wall motion abnormalities, anteroseptal fractional shortening and % area reduction averaged20% less (p = 0.03 for area reduction) at 30 minutes versus controls. Only 50% of group I or II rabbits with LV anteroseptal wall motion abnormalities had intraventricular conduction disturbances. Radioactive microsphere flow studies (n = 6) 1 minute after a 4 mg/kg cocaine bolus revealed an equivalent decrease (10% to 20%, average) in septal and LV free wall perfusion (p value not significant). Electron microscopy revealed myocardial cell contraction band necrosis in 3 and sarcoplasmic reticular edema in 7 of 10 cocaine rabbits (unrelated to dose). We conclude that acute cocaine administration in rabbits frequently produces LV anteroseptal wall motion abnormalities even in the absence of differentially decreased perfusion or intraventricular conduction disturbances and produces ultrastructural abnormalities of the myocytes. These findings suggest a direct, nonuniform effect of cocaine on the LV myocardium.

Doppler imaging of the myocardium is a new application which has the potential to record myocardial velocities. These recorded velocities, however, include cardiac motion independent of ventricular contraction. A measured myocardial velocity, therefore, represents the net vector of contraction, translation, and rotation. To determine the effects of cardiac translation on myocardial velocities, 2-dimensional (2D) and M-mode echocardiographic recordings were obtained in 10 normal subjects. The average anteroseptal (AS) and posterior wall (PW) velocities were measured by 2D echo directed M-mode in the centerline of the parasternal short-axis view. Translation was measured from 2D echo cine-loop display as the displacement of the epicardial junction of the right ventricular free wall and interventricular septum during systole. The average translational velocity is reported as the component of the displacement vector parallel to the M-mode beam (+ = toward transducer). The AS and PW velocities (cm/sec) displayed in the table represent net measured velocities, which include the translational vector. Results AS PW Translation Mean ± SD 3.2 ± 0.5 4.5 ± 1.1 +1.3 ± 0.6 Range 2.4 to 4.0 3.4 to 6.9 -l.4 to + 2.4 In 8/10 subjects the velocity vector was positive. The mean percent error in the M-mode derived velocities due to translation was 41% for the AS wall and 31% for the PW. Conclusions 1) As measured by 2D echocardiography, the magnitude of the translational vector is significant when compared to the M-mode derived myocardial velocities. 2) The relative error demonstrated in the measured velocities may be further modified when applied in two dimensions, due to the angle of incidence of the Doppler beam. 3) New techniques for measuring myocardial velocities, such as Doppler imaging of the myocardium, should incorporate algorithms which correct for the translational vector.

In the investigation of new antiarrhythmic drugs, comparative trials with clinically available antiarrhythmic agents provide a perspective from which to judge the new investigational agent. Two clinical investigations of moricizine HCl, each using a placebo-controlled, double-blind, crossover design, are summarized. In the first study, 18 patients with greater than or equal to 30 ventricular premature complexes (VPCs) per hour (mean 369 +/- 95) were given propranolol (120 mg daily) compared with moricizine HCl (816 +/- 103 mg daily). Propranolol suppressed 38% of VPCs in the study group, moricizine HCl, 81% of VPCs, and the combination of both drugs, 87%. Moricizine HCl was more effective than propranolol in suppressing VPCs at all individual levels greater than 70% (p less than 0.05, McNemar's test). The combination of moricizine HCl and propranolol was well tolerated. The second investigation used a placebo-controlled, double-blind, crossover design to compare the efficacy of disopyramide (600 mg daily) and moricizine HCl (800 mg daily) in 27 patients. Patients had greater than or equal to 40 VPCs/hr on a 24-hour ambulatory electrocardiogram. During moricizine HCl administration, the mean VPC frequency decreased from 524 to 151 VPCs/hr (71.2% reduction). In contrast, disopyramide reduced VPC frequency from 535 to 253 VPCs/hr (52.8% reduction) and demonstrated significantly greater side effects (p less than 0.05). Moricizine HCl was more effective than disopyramide in suppressing VPCs at all individual percent reduction levels greater than 70% (p less than 0.05, McNemar's test). Moricizine HCl was more effective in suppressing VPCs than either disopyramide or propranolol, with significantly fewer side effects.

A 51 year old man with an innominate artery aneurysm presented with claudication and ischemia of the right forearm and hand. Two-dimensional echocardiography visualized the saccular aneurysm and a pedunculated mobile thrombus within it that were not seen during aortic arch angiography. Two-dimensional echocardiography, shown to be useful in identifying intracardiac masses and aortic aneurysms, may be important in selecting patients with increased risk of embolization.