Myocardial Rupture in Acute Myocardial Infarction: Mechanistic Explanation Based on the Ventricular Myocardial Band Hypothesis.

BACKGROUND: Torrent-Guasp explains the structure of the ventricular myocardium by means of a helical muscular band. Our primary purpose was to demonstrate the utility of echocardiography in human and porcine hearts in identifying the segments of the myocardial band. The second purpose was to evaluate the relation of the topographic distribution of the myocardial band with some post-myocardial infarction ruptures. METHODS: Five porcine and one human heart without cardiopathy were dissected and the ventricular myocardial segments were color-coded for illustration and reconstruction purposes. These segments were then correlated to the conventional echocardiographic images. Afterwards in three cases with post-myocardial infarction rupture, a correlation of the topographic location of the rupture with the distribution of the ventricular band was made. RESULTS: The human ventricular band does not show any differences from the porcine band, which confirms the similarities of the four segments; these segments could be identified by echocardiography. In three cases with myocardial rupture, a correlation of the intra-myocardial dissection with the distribution of the ventricular band was observed. CONCLUSIONS: Echocardiography is helpful in identifying the myocardial band segments as well as the correlation with the topographic distribution of some myocardial post-infarction ruptures.

Predictors of heart failure in patients with stable coronary artery disease: a PEACE study.

BACKGROUND: Heart failure (HF) is a disease commonly associated with coronary artery disease. Most risk models for HF development have focused on patients with acute myocardial infarction. The Prevention of Events with Angiotensin-Converting Enzyme Inhibition population enabled the development of a risk model to predict HF in patients with stable coronary artery disease and preserved ejection fraction. METHODS AND RESULTS: In the 8290, Prevention of Events with Angiotensin-Converting Enzyme Inhibition patients without preexisting HF, new-onset HF hospitalizations, and fatal HF were assessed over a median follow-up of 4.8 years. Covariates were evaluated and maintained in the Cox regression multivariable model using backward selection if P<0.05. A risk score was developed and converted to an integer-based scoring system. Among the Prevention of Events with Angiotensin-Converting Enzyme Inhibition population (age, 64+/-8; female, 18%; prior myocardial infarction, 55%), there were 268 cases of fatal and nonfatal HF. Twelve characteristics were associated with increased risk of HF along with several baseline medications, including older age, history of hypertension, and diabetes. Randomization to trandolapril independently reduced the risk of HF. There was no interaction between trandolapril treatment and other risk factors for HF. The risk score (range, 0 to 21) demonstrated excellent discriminatory power (c-statistic 0.80). Risk of HF ranged from 1.75% in patients with a risk score of 0% to 33% in patients with risk score >or=16. CONCLUSIONS: Among patients with stable coronary artery disease and preserved ejection fraction, traditional and newer factors were independently associated with increased risk of HF. Trandolopril decreased the risk of HF in these patients with preserved ejection fraction.

Detection of coronary artery disease with perfusion stress echocardiography using a novel ultrasound imaging agent: two Phase 3 international trials in comparison with radionuclide perfusion imaging.

AIMS: To determine if perfusion stress echocardiography (PSE) with Imagify (perflubutane polymer microspheres) is comparable to stress perfusion imaging using (99m)Tc single photon emission computed tomography (SPECT) for coronary artery disease (CAD) detection. PSE is a novel technique for evaluating myocardial perfusion. RAMP (real-time assessment of myocardial perfusion)-1 and -2 were international, Phase 3 trials that evaluated the ability of PSE with Imagify, to detect CAD. METHODS AND RESULTS: Chronic, stable, chest pain patients (n=662) underwent Imagify PSE and gated SPECT imaging at rest and during dipyridamole stress. Independent blinded cardiologists [three PSE readers per trial, and four SPECT readers (one for RAMP-1, three for RAMP-2)] interpreted images. CAD was defined by quantitative coronary angiography or 90-day outcome with clinical review. Accuracy, sensitivity, and specificity were evaluated using non-inferiority analysis (one-sided alpha=0.025) compared with SPECT. SPECT results for RAMP-1 and -2 were: accuracy (70%, 67%), sensitivity (78%, 61%), and specificity (64%, 76%). Accuracy of all six PSE readers was non-inferior to SPECT (66-71%, P

Dissecting intramyocardial hematoma: clinical presentation, pathophysiology, outcomes and delineation by echocardiography.

BACKGROUND: In large necropsy studies dissecting intramyocardial hematoma (DIH) with serpiginous tracts across the myocardial fibers has been reported in both the septum and the left ventricle free wall. METHODS: We studied 15 patients admitted to the hospital with acute myocardial infarction (AMI) in which DIH was demonstrated by either transthoracic and/or transesophageal and confirmed intraoperatively or by necropsy. RESULTS: In nine patients the hemorrhagic dissection was predominantly in the septum and in the remaining it was in the free wall of the left ventricle (LV). Myocardial infarction involved the left ventricular inferior wall in two, and the anterior wall in 13 patients. The overall mortality was 47%, and in the group with septal hematoma it reached to 78%. Echocardiography disclosed the various acoustic densities of the evolving intramyocardial hematoma, its extension through the hemorrhagic dissection, its spontaneous reabsorption, as well as its communication with the ventricular cavities. CONCLUSIONS: Echocardiography is the method of choice for the noninvasive diagnosis of patients with suspected myocardial rupture and intramyocardial dissection postmyocardial infarction.

Sudden cardiac death in patients with stable coronary artery disease and preserved left ventricular systolic function.

Although sudden cardiac death (SCD) has been extensively studied in patients with coronary artery disease (CAD) and low ejection fraction, prediction of SCD among individuals with preserved left ventricular systolic function is less well understood. We randomized 8,290 patients with stable CAD with preserved left ventricular systolic function to trandolapril or placebo in a secondary coronary prevention trial, and we used Cox proportional hazards models to identify independent baseline predictors of SCD during 4.8 year follow-up (median). Using a risk scoring algorithm based on simple clinical characteristics, we were able to distinguish individuals at higher risk for SCD. Independent determinants of SCD included age (p <0.001), current angina pectoris (p = 0.002), ejection fraction >40% to <50% (as opposed to >50%) (p <0.001), and diuretic (p <0.001) and digitalis use (p <0.001). Negative predictors included having prior coronary revascularization (p = 0.01) and being female (p = 0.02) or Caucasian (p = 0.006). Trandolapril neither increased nor decreased SCD. Thus, among patients with stable CAD with preserved left ventricular systolic function receiving current standard-of-care including coronary revascularization, clinical characteristics can identify individuals at higher risk for SCD.

Carbon monoxide donors or heme oxygenase-1 (HO-1) overexpression blocks interleukin-18-mediated NF-kappaB-PTEN-dependent human cardiac endothelial cell death.

The objective of this study was to determine whether heme oxygenase-1 (HO-1) or heme metabolites exert cytoprotective effects on interleukin-18-mediated endothelial cell (EC) death. Treatment with interleukin (IL)-18 increased NF-kappaB activation and PTEN induction, suppressed Akt activation, and stimulated EC death. While ectopic expression of p65 enhanced PTEN transcription, adenoviral transduction of dnIkappaB-alpha, dnp65, or dnIKKbeta was inhibitory. Furthermore, IL-18 suppressed HO-1 mRNA expression via enhanced mRNA degradation. Overexpression of HO-1, treatment with HO-1 inducer hemin, or the CO donor cobalt (III) protoporphyrin IX all reversed IL-18-mediated NF-kappaB activation, PTEN induction, Akt suppression, and EC death. Furthermore, hemin induced HO-1 expression, and HO-1 knockdown, HO-1 inhibition, or CO scavengers all reversed the prosurvival effects of hemin. In addition, the CO donors CORM-1 and CORM-3 and the heme metabolites biliverdin and bilirubin attenuated IL-18-induced EC death via a similar signaling pathway. IL-18 induced p38alpha MAPK activation, and suppressed p38beta isoform expression. While p38alpha knockdown attenuated, p38beta knockdown potentiated IL-18-mediated EC death. Hemin and HO-1 reversed IL-18-mediated p38alpha induction and restored p38beta levels. These results demonstrate that IL-18 suppresses HO-1 expression and induces EC death. HO-1 overexpression, HO-1 induction, or treatment with heme metabolites all reverse IL-18-mediated p38alpha MAPK and NF-kappaB activation, PTEN induction, Akt suppression, and EC death. Thus, HO-1 inducers and CO donors may have the therapeutic potential to effectively block IL-18 signaling and reduce IL-18-dependent vascular injury and inflammation.

Can patients at elevated risk of stroke treated with anticoagulants be further risk stratified?

BACKGROUND AND PURPOSE: Patients with atrial fibrillation have a varied risk of stroke, depending on age and comorbid conditions. The objective of this study was to assess the predictive value of stroke risk classification schemes and to identify patients with atrial fibrillation who are at substantial risk of stroke despite optimal anticoagulant therapy. METHODS: Seven recognized classification schemes-the American College of Chest Physicians 2001, American College of Chest Physicians 2004, Stroke Prevention in Atrial Fibrillation (SPAF), Atrial Fibrillation Investigators, Framingham, van Walraven, and CHADS(2)-were compared for their ability to predict ischemic stroke in patients receiving anticoagulant therapy. Data came from the Stroke Prevention using an ORal Thrombin Inhibitor in atrial Fibrillation III and V trials, which compared the efficacy of adjusted-dose warfarin and the direct thrombin inhibitor ximelagatran (36 mg twice daily) in preventing thromboembolic events in 7329 patients with chronic or paroxysmal nonvalvular atrial fibrillation who were at moderate or high risk of ischemic stroke. The main outcome measure was ischemic stroke, as determined by a central event adjudication committee. RESULTS: During 11 245 patient-years of follow-up, 159 patients had an ischemic stroke (1.4%/year). As indicated by c statistics and hazard ratios, 3 of the classification schemes predicted stroke significantly better than chance: Framingham (c=0.64), CHADS(2) (c=0.65), and SPAF (c=0.61). CONCLUSIONS: In a large cohort of atrial fibrillation patients at moderate or high risk of ischemic stroke treated with warfarin or ximelagatran, the CHADS(2), SPAF, and Framingham schemes had greater predictive accuracy than chance. This predictive ability may allow clinicians to target high-risk patients for more aggressive intervention.

Long-term follow-up of intramyocardial dissecting hematomas complicating acute myocardial infarction.

Intramyocardial dissecting hematoma is a form of subacute cardiac rupture complicating acute myocardial infarction. Initially contained within the myocardial wall, the hematoma may expand, rupture into adjacent structures, or spontaneously resolve. However, long-term follow-up is unknown because clinical and serial imaging data are lacking. The purpose of this study was to characterize the early and late myocardial wall changes after transmural myocardial infarction using serial ultrasound examinations of the infarct-related segments. Clinical, electrocardiographic, and echocardiographic features of 8 patients (7 men, mean age 59 years) who presented with acute myocardial infarction and echocardiographically documented intramyocardial dissecting hematoma were analyzed. All patients had precordial echocardiography and 6 underwent transesophageal echocardiography. Differentiating hematoma from trabeculations, thrombus, or pseudoaneurysm was done with contrast and color flow Doppler. Seven patients presented with S-T elevation in V1 to V4, and in 3 the elevation extended to V5, V6, I, and aVL. One patient presented with S-T elevation in II, III, aVF, V3R, and V4R. The most striking feature was persistent S-T elevation of more than 72 hours in all patients. Hematoma consisted of a cysticlike, echolucent cavity variable in size, adjacent to severely hypokinetic or dyskinetic infarct-related segments. Hematoma acoustic characteristics depended on time of evolution. Two patients underwent elective revascularization and the rest were medically treated. Two patients died and 6 were alive at the mean follow-up of 12 months. In conclusion, persistent S-T elevation is an important clue in suggesting intramyocardial dissecting hematoma, which is confirmed by its unique ultrasound appearance. Serial echocardiography is useful in determining its evolving nature, and may guide outcome.

[Contrast echocardiography in myocardial perfusion today]. / Estado actual de la ecocardiografía de contraste en la perfusión miocárdica.

Advances in ultrasonic engineering have made possible the development of "intelligent" microparticles with the capacity of passing through the pulmonary circulation in sufficient amount to acquire images of the left heart, making possible the evaluation of myocardial perfusion. Although the Food and Drug Administration of the United States has approved several contrast agents for use in ventricular opacification and visualization of endocardial borders in subjects that have suboptimal studies, at this time, it has not approved any agent of contrast for use in myocardial perfusion. Currently, there are two multicenter studies on a great scale that were exclusively designed for myocardial perfusion in comparison with nuclear medicine and angiography. Our laboratory has had the opportunity to actively participate in both trials. This revision includes the design, interpretation criteria, and preliminary results of CARDIOsphere. As well, we are presenting the interpretation criteria of the AI-700 bubble, which is currently in phase III of clinical investigation. Myocardial perfusion assessment with contrast echocardiography faces several challenges that need to be addressed before it becomes established as an efficient alternative. A common limitation is the viability of this method in subjects with bad acoustic window, the creation of intrinsic artifacts to the system, as distal and lateral attenuation; the unavoidable learning curve, and the settlement of defect quantification criteria.

Risk factors, echocardiographic patterns, and outcomes in patients with acute ventricular septal rupture during myocardial infarction.

Ventricular septal rupture (VSR), which can complicate an acute myocardial infarction (MI), carries a high mortality rate. Because precordial and transesophageal echocardiography can identify the type of rupture and assess right ventricular (RV) function at the patient's bedside, we examined the prognostic significance of echocardiographic patterns in postinfarct VSR by postulating that complex rupture and RV involvement carry a worse prognosis. Seventeen patients (10 men; mean age 66 years) who had confirmed postinfarct VSR underwent precordial and transesophageal echocardiography followed by coronary angiography. Serial 12-lead and right precordial leads were also available. Type of septal rupture was classified as simple or complex based on autopsy-proved echocardiographic criteria. Three patients had inferior wall MI and 14 had anterior wall MI. ST-segment elevation persisted >72 hours in all 3 patients who had inferior wall MI and in 12 who had anterior wall MI. Segmental wall motion abnormalities helped in detecting the left ventricular entry site, and use of unconventional views superimposed with color flow Doppler provided the RV exit site. RV function was better appreciated with transesophageal echocardiography. Two patients who had inferior wall MI and 7 who had anterior wall MI had complex ruptures. All 3 patients who had inferior wall MI and 7 who had anterior wall MI had electrocardiographic and echocardiographic evidence of RV involvement. Mortality rate was higher in patients who had complex rupture (78% vs 38%, p <0.001) and in those who had RV extension (71% vs 29%, p <0.001). In conclusion, persistent ST elevation is a common finding in patients who have postinfarct VSR. Complex VSR and RV involvement are significant determinants of clinical outcome.

Estado actual de la ecocardiografía de contraste en la perfusión miocárdica / Contrast echocardiography in myocardial perfusion today

Avances en la ingeniería ultrasónica han llevado a la creación de micropartículas "inteligentes" con capacidad de atravesar en cantidad suficiente la barrera pulmonar transcapilar para permitir la obtención de imágenes de corazón izquierdo, lo que ha hecho posible la evaluación de la perfusión miocárdica. Si bien la Food and Drug Administration de los Estados Unidos ha aprobado varios agentes de contraste para empleo en opacificación ventricular y visualización de bordes endocárdicos en sujetos que tienen estudios subóptimos, no ha aprobado hasta el momento ningún agente de contraste para uso en perfusión miocárdica. En la actualidad existen dos estudios multicéntricos a gran escala que fueron diseñados exclusivamente para perfusión miocárdica en comparación con medicina nuclear y coronariografía. Nuestro laboratorio ha tenido la oportunidad de participar activamente en ambos estudios. Esta revisión incluye el diseño, criterios de interpretación y resultados preliminares de CARDIOsphere. Además, presentamos criterios de interpretación del estudio con la burbuja AI-700 que se encuentra actualmente en fase III de investigación clínica. La ecocardiografía de contraste para perfusión miocárdica enfrenta varios retos que deberá resolver antes de que se establezca como una alternativa eficiente. Una limitante común es la aplicabilidad de este método en sujetos con mala ventana acústica, la creación de artefactos intrínsecos al sistema como son la atenuación distal y lateral, la inevitable curva de aprendizaje, y el establecimiento de criterios en la cuantificación de los defectos.

Advances in ultrasonic engineering have made possible the development of "intelligent" micro-particles with the capacity of passing through the pulmonary circulation in sufficient amount to acquire images of the left heart, making possible the evaluation of myocardial perfusión. Although the Food and Drug Administration of the United States has approved several contrast agents for use in ventricular opacification and visualization of endocardial borders in subjects that have sub-optimal studies, at this time, it has not approved any agent of contrast for use in myocardial perfusión. Currently, there are two multicenter studies on a great scale that were exclusively designed for myocardial perfusión in comparison with nuclear medicine and angiography. Our laboratory has had the opportunity to actively participate in both trials. This revision includes the design, interpretation criteria, and preliminary results of CARDIOsphere. As well, we are presenting the interpretation criteria of the AI-700 bubble, which is currently in phase III of clinical investigation. Myocardial perfusión assessment with contrast echocardiography faces several challenges that need to be addressed before it becomes established as an efficient alternative. A common limitation is the viability of this method in subjects with bad acoustic window, the creation of intrinsic artifacts to the system, as distal and lateral attenuation; the unavoidable learning curve, and the settlement of defect quantification criteria. (Arch Cardiol Mex 2005; 75: 197-209).

Myocardial contrast echocardiography in assessing microcirculation in baboons with chagas disease.

OBJECTIVE: Microvascular abnormalities have been postulated in the pathogenesis of chagasic cardiomyopathy. The objective of this study was to evaluate the relationship between coronary microcirculation and systolic function impairment in baboons with Chagas disease using myocardial contrast echocardiography (MCE). METHODS: Seventeen seropositive (5 males, 12 females; mean age 20 years) and 13 age- and gender-matched seronegative baboons underwent MCE using intravenous octafluoropropane human albumin microspheres. Color-coding was used to enhance tissue contrast in assessing regional myocardium uniformity and texture. Dipyridamole (0.54 mg/kg) was given to a subset of 4 animals to challenge coronary flow reserve. Systolic indices included left ventricular fractional shortening, velocity of circumferential fiber shortening, and left and right ventricular ejection fractions. RESULTS: Four of the 17 (24%) seropositive primates had decreased fractional shortening (25 +/- 8% vs. 40 +/-5%, p <.005), velocity of circumferential fiber shortening (1.05 +/- 0.36 circ/s vs. 1.84 +/- 0.23 circ/s, p <.0001), and reduced right ventricular ejection fraction (44 +/- 9% vs. 54 +/- 4%, p <.05) compared to other seropositive animals. Seropositive and seronegative groups showed no significant differences on the coronary microcirculation pattern as evaluated by MCE, including the 4 baboons with systolic function impairment. Moreover, coronary flow vasoreactivity resulted in a significant increase in myocardial flow as detected by color-coding masking. CONCLUSIONS: Chagasic heart disease is present in 24% of seropositive baboons spontaneously infected with Trypanosoma cruzi. MCE reveals a discrepancy between coronary microcirculation at rest and alterations in myocardial contractility, suggesting preservation of the microvascular integrity in this unique animal model.

Analysis of cause-specific mortality in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study.

BACKGROUND: Expectations that reestablishing and maintaining sinus rhythm in patients with atrial fibrillation might improve survival were disproved in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study. This report describes the cause-specific modes of death in the AFFIRM treatment groups. METHODS AND RESULTS: All deaths in patients enrolled in AFFIRM underwent blinded review by the AFFIRM Events Committee, and a mode of death was assigned. In AFFIRM, 2033 patients were randomized to a rhythm-control strategy and 2027 patients to a rate-control strategy. During a mean follow-up of 3.5 years, there were 356 deaths in the rhythm-control patients and 310 deaths in the rate-control patients (P=0.07). In the rhythm-control group, 129 patients (9%) died of a cardiac cause, and in the rate-control group, 130 patients (10%) died (P=0.95). Both groups had similar rates of arrhythmic and nonarrhythmic cardiac deaths. The numbers of vascular deaths were similar in the 2 groups: 35 (3%) in the rhythm-control group and 37 (3%) in the rate-control group (P=0.82). There were no differences in the rates of ischemic stroke and central nervous system hemorrhage. In the rhythm-control group, there were 169 noncardiovascular deaths (47.5% of the total number of deaths), whereas in the rate-control arm, there were 113 noncardiovascular deaths (36.5% of the total number of deaths) (P=0.0008). Differences in noncardiovascular death rates were due to pulmonary and cancer-related deaths. CONCLUSIONS: Management of atrial fibrillation with a rhythm-control strategy conferred no advantage over a rate-control strategy in cardiac or vascular mortality and may be associated with an increased noncardiovascular death rate.

Electrocardiographic findings in naturally acquired chagasic heart disease in nonhuman primates.

The significance of electrocardiographic (ECG) changes described in animals with Chagas' disease is questionable in view that other non-invasive comparisons have been lacking. 12-lead ECG and two-dimensional echocardiography (echo) was performed in 17 seropositive and 13 seronegative baboons. Similar to humans, a wide variety of ECG outcomes were observed in the infected animals. Standard ECG measurements were not different between groups. Five seropositive (29%) and 3 seronegative (23%) animals had low voltage; 4 seropositives (24%) and 2 (15%) seronegatives had tall P-waves. Precordial Q waves were seen in 10 seropositives (59%) and in 7 (54%) seronegatives without septal abnormalities on two-dimensional echo. One seropositive animal had a 2(nd) degree (Wenckebach) AV block and left anterior fascicular block. Most animals in both groups had diffuse T-wave abnormalities. Echo evidence of systolic dysfunction was found in 4 seropositives and in none of the controls; thus, chagasic heart disease was present in 24% of naturally infected baboons. Since most non-human primates, irrespective of their serology, have diffuse, nonspecific ECG changes not necessarily diagnostic of myocardial disease, two-dimensional echo should be added to their non-invasive assessment.

Morphologic and functional characterization of Chagasic heart disease in non-human primates.

Chagasic heart disease has been documented in non-human primates, but noninvasive characterization of systolic and diastolic function has not been previously reported. Seventeen seropositive (12 females; mean age, 20) and 13 age- and gender-matched seronegative baboons underwent Doppler echocardiography. Systolic function indices included left ventricular (LV) fractional shortening (FS %), velocity of circumferential fiber shortening (VCF, circ/sec), LV mass index, and left and right ventricular ejection fractions (RVEF %). Diastolic function indices included transmitral E-wave, A-wave, E/A ratio, E-deceleration time, and isovolumic relaxation time. Twelve-lead electrocardiographic (ECG) recordings were obtained. There were no significant differences between groups for body size or blood pressure. Seropositive and seronegative groups revealed diffuse non-specific T wave changes precluding differentiation; however, tall "P" waves were seen in four seropositive and two seronegative baboons. Four of the 17 (24%) seropositive baboons had decreased FS (25 +/- 8% versus 40 +/- 5%, P < 0.005) and VCF (1.05 +/- 0.36 circ/sec versus 1.84 +/- 0.23 circ/sec, P < 0.0001), prolonged isovolumic relaxation time (71 +/- 16 msec versus 55 +/- 9 msec, P < 0.02), and reduced RVEF (44 +/- 9% versus 54 +/- 4%, P < 0.05), as compared with the other seropositive baboons. We conclude that chagasic heart disease is present in 24% of the naturally infected baboons in this study. ECG evidence of right atrial enlargement was more common in the seropositive animals. There were systolic and diastolic abnormalities of both ventricles. The LV systolic dysfunction may be segmental or diffuse.

Comparison of real-time coherent contrast imaging to dipyridamole thallium-201 single-photon emission computed tomography for assessment of myocardial perfusion and left ventricular wall motion.

Real-time coherent contrast imaging (CCI) echocardiography has the ability to evaluate wall motion and myocardial perfusion simultaneously, but its clinical applicability in the diagnosis of coronary artery disease (CAD) remains to be determined. This study examines the level of agreement between real-time CCI echocardiography and thallium-201 single-photon emission computed tomography (SPECT) following stress vasodilation. Forty-two patients with known or suspected CAD underwent real-time CCI using octafluoropropane-filled microspheres infusion before and after dipyridamole and thallium-201 injections. The apical 4- and 2-chamber views were each divided into 6 segments to assess wall motion and perfusion. Real-time CCI and SPECT were interpreted independently. Thirty-eight patients successfully completed tests, and 4 had suboptimal contrast images. Each vascular territory was classified as normal or abnormal by CCI perfusion, wall motion, and SPECT at baseline and at stress. Of the 114 territories (3 in each of the 38 patients), 3 (3.5%) were not analyzed; however, all territories corresponding to the left anterior descending artery were suitable for analysis. Concordance between CCI echocardiography and thallium-201 SPECT perfusion for left anterior descending, left circumflex, and right coronary artery territories were 91%, 86%, and 69%, respectively; between CCI perfusion and wall motion, the correlations were 93%, 93%, and 91%, respectively. When CCI perfusion and wall motion analysis were combined, their concordance to thallium-201 SPECT uptake improved to 94%, 89%, and 79%, respectively. In conclusion, real-time CCI echocardiography agrees very closely with thallium-201 SPECT in assessing myocardial perfusion following vasodilatory stress. Assessment of myocardial perfusion, in addition to segmental wall motion analysis, during stress echocardiography may be a significant contribution to the noninvasive evaluation of patients with ischemic heart disease.

Localization of a coronary artery fistula using contrast transesophageal echocardiography.

With the increasing use of transesophageal and other cardiac imaging, coronary fistulas are being discovered more often. The clinical significance of these communications is unclear. Microbubble echo-contrast has been used to enhance endocardial definition, myocardial perfusion, and augment Doppler signals. This case describes the use of microbubbles to enhance the color Doppler signals to better define location and extent of a coronary artery fistula communicating with the left ventricle.