Bernier, Mathieu

ObjectivesThe aim of our study was to demonstrate that the use of contrast microbubbles during transesophageal echocardiography (TEE) guided cardioversion will improve interpretation of the TEE images.BackgroundTEE‐guided cardioversion of atrial flutter or fibrillation (AF) is a safe and proven method to restore sinus rhythm. However, artifacts and dense spontaneous echo contrast in the left atrial appendage (LAA) can sometimes decrease the level of confidence in excluding the presence of thrombus.MethodsOne hundred patients referred for TEE‐guided cardioversion were prospectively enrolled and microbubble contrast agent (DEFINITY) was administered after the clinical decision had been made regarding suitability for cardioversion. Noncontrast and contrast images were compared during subsequent offline analysis.ResultsLAA dimensions and contractility indices were higher, artifacts were significantly differentiated, previously unsuspected LAA filling defects were identified, and the level of confidence in excluding thrombus was enhanced in the contrast images when compared to the noncontrast images. After 4 months follow‐up, 1 stroke‐associated death occurred in a patient who had LAA thrombus recognized only by contrast. Left atrial appendage visualization is enhanced with microbubble contrast agent use during transesophageal echocardiography guided cardioversion and is useful in identification of intracardiac thrombus.

Purrpose: To evaluate myocardial microvascular disease in patients with type 2 diabetes mellitus (DM) using myocardial contrast echocardiography (MCE) and to report on its diagnostic accuracy using single photon emission tomography (SPECT) as reference test. Methods: We prospectively enrolled 79 patients (25 DM; 66±11 years) who underwent simultaneous SPECT and MCE with contrast agent during adenosine stress. MCE and SPECT were visually analyzed using 17 segments. Quantitative MCE parameters were derived from replenishment curves. Microbubble velocity (β min −1 ), absolute myocardial blood flow (MBF ml/min/g), and reserve values were calculated. Diagnostic accuracy and area under curve (AUC) was reported. Results: Patients with DM had higher BMI vs non DM (33±7 vs 28±5kg/m 2 P=0 .007), with more prior myocardial infarction (40 vs 15% P=.01). Visual MCE was abnormal in 40 (51%) patients (60% in DM vs 46% in non DM P=0.04). SPECT was abnormal in 38 (48%) patients [60% in DM vs 42% non DM, P=0.01]. Reserve parameters were lower in DM vs. non DM patients: (β 1.77±1.12 vs 2.20±1.4, P<0.001 and MBF 2.86± 2.62 vs. 3.67±2.84, P<0.001). DM patients without CAD on SPECT had significantly lower β, and MBF reserve compared to non DM patients without CAD. Compared to SPECT, β reserve cutoff 1.6 had AUC 0.817, sensitivity 81%, and specificity 66% while MBF reserve cutoff 1.9 had AUC 0.760, sensitivity 79%, and specificity 63% in DM patients. Conclusion: Diabetes is associated with myocardial microvascular abnormalities as evidenced by abnormal myocardial perfusion on visual and quantitative MCE.

Background— Microbubble safety concerns led to changes in product recommendations for patients with pulmonary hypertension. Noninvasive estimation of right ventricular systolic pressure (RVSP) is equivalent to pulmonary artery systolic pressure in the absence of pulmonary outflow obstruction. We analyzed the short- and long-term outcomes of patients who received microbubble contrast and those who did not during stress echocardiography (SE) according to resting RVSP. Methods and Results— From November 2003 to December 2007, 26 774 patients underwent SE. RVSP (mean, 32.6�9.6 mm Hg) was measured in 16 434 patients. Of these, 6164 (37.5%) received contrast for left ventricular opacification and 10 270 (62.5%) did not. Short-term (≤72 hours and ≤30 days) and long-term (4.3 years) end points were death and myocardial infarction. Analysis was done for rest RVSP cut-points ≥35, ≥50, and ≥60 mm Hg and tricuspid regurgitant velocities ≥2.7 ms −1 and ≥3.5 ms −1 . Adjusted Cox regression models were used. The contrast cohort comprised older patients (age, 67�12 versus 64�14 years; P <0.001), who were more likely to have positive SE results (35% versus 30%, P <0.001) compared with the noncontrast cohort. Using RVSP ≥50 mm Hg, there was no significant difference in short-term events between the contrast and noncontrast cohorts. For long-term events, there was no significant difference between both cohorts (adjusted hazard ratios [95% confidence intervals] for death, 1.10 [0.80 to 1.50], P =0.56; and myocardial infarction, 0.34 [0.11 to 1.03], P =0.06). Similar results were obtained at different RVSP and tricuspid regurgitant cut-points. Contrast agent–related adverse effects occurred in <1% of patients. Conclusion— RVSP had no impact on predisposition to adverse outcomes in patients undergoing contrast SE in the population studied.

Object The pathophysiology of myocardial dysfunction after subarachnoid hemorrhage (SAH) remains unclear. Using myocardial real-time perfusion contrast echocardiography (RTP-CE), the authors evaluated microvascular function in patients with acute SAH. Methods Over a 15-month period, 10 patients with acute SAH and evidence of cardiac dysfunction were prospectively enrolled. The authors performed RTP-CE within 48 hours of SAH diagnosis. Wall motion and myocardial perfusion were evaluated in 16 left ventricle segments. Qualitative and quantitative RTP-CE analyses were conducted to compare patients with and without regional wall motion abnormalities (RWMAs). Follow-up RTP-CE at a mean of 53.7 ± 43 days was undertaken in patients with baseline RWMAs. Results Ten patients with SAH and evidence of cardiac dysfunction were prospectively enrolled. There were 3 men and 7 women whose mean age was 63.5 ± 10.1 years. The authors documented evidence of RWMAs in 6 patients. Normal perfusion was demonstrated by RTP-CE in all patients at baseline and follow-up, despite the presence of RWMAs. Compared with patients presenting with normal wall motion, in patients with RWMAs there was a trend for higher quantitative RTP-CE parameters, suggesting hyperemia with mean myocardial blood flow velocity (β, s−1) of 1.08 ± 0.61 (95% CI 0–2.61) compared with 1.62 ± 0.64 (95% CI 0.94–2.29) and myocardial blood flow (A × β, dB/s) of 0.99 ± 0.41 (95% CI 0–2.0) versus 1.63 ± 0.86 (95% CI 0.72–2.53). Follow-up RTP-CE was feasible in 3 patients with RWMAs. Regional systolic function was restored in those who completed follow-up. Conclusions The authors found that RTP-CE readily evaluates microvascular function in patients with SAH. Wall motion and perfusion dissociation were observed. Quantitative RTP-CE showed a trend for microvascular hyperemia in patients with RWMAs, suggesting that post-SAH myocardial dysfunction could occur in the absence of microvascular dysfunction.