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Background Diastolic dysfunction is common immediately after coronary artery bypass surgery (CABG). The duration of this phenomenon is unknown. Intravenous calcium is frequently administered during separation from cardiopulmonary bypass (CPB). We sought to determine whether intravenous calcium influences perioperative diastolic function and whether diastolic dysfunction persists into the postoperative period. Methods and results Patients undergoing first-time elective CABG (n = 29) were randomly assigned to receive intravenous calcium chloride (n = 13) or placebo (n = 16) during separation from CPB. Diastolic function was assessed by the pressure-area relation with transesophageal echocardiography and pulmonary capillary wedge pressure (PCWP) measured simultaneously. Left ventricular end-diastolic area (LVEDA) and Doppler indexes were measured at comparable PCWP (within 2 mm Hg) at baseline, after separation from CPB, after sternal closure, and 3 hours after surgery. After CABG, both groups had a significant decrease in LVEDA and mitral E-wave deceleration time that persisted at 3 hours. Because there were no significant differences between the calcium and control groups at any time point, the data for the entire study cohort was analyzed. The LVEDA decreased (stiffness increased) progressively from 16.9 ± 3.4 cm 2 at baseline to 15.8 ± 2.9 cm 2 after CPB, 14.9 ± 2.5 cm 2 after sternal closure, and 14.3 ± 3.1 cm 2 at 3 hours after surgery ( P P = .0001). Conclusions An increase in left ventricular diastolic chamber stiffness is nearly universal after CABG, and it persists for at least 3 hours after surgery. An intravenous bolus of calcium chloride given during separation from CPB has no measurable negative effect on diastolic function. In the setting of increased chamber stiffness, the PCWP alone does not adequately reflect the volume status and effective preload of the left ventricle.

Background Remodeling of the left ventricle with the development of a spherical cavity occurs in dilated cardiomyopathy and is associated with a poor long-term prognosis. The early effects of myocarditis on left ventricular geometry have not been previously described or correlated with clinical outcome. Methods The baseline echocardiograms of 35 patients with biopsy-confirmed myocarditis were compared with 20 normal controls. Left ventricular end-diastolic volume, long axis length, and mid-cavity diameter were measured. The degree of sphericity was expressed as the ratio of the mid-cavity diameter to the long axis length. Left ventricular ejection fraction was assessed by radionuclide angiography. Results In patients with myocarditis, mean left ventricular volume of 81 ± 29 mL/m 2 was significantly greater than 50 ± 8 mL/m 2 in controls ( P = .001). Chamber dilatation occurred primarily along the mid-cavity diameter, which measured 5.3 ± 0.8 cm in patients with myocarditis versus 4.2 ± 0.4 cm in controls ( P = .001). The degree of left ventricular sphericity in patients with myocarditis, 0.64 ± 0.08, was significantly greater than that of controls, 0.54 ± 0.04 ( P = .001). When patients were stratified according to left ventricular volume, patients with increased left ventricular volume (>75 mL/m 2 ) were associated with a more spherical chamber and lower left ventricular ejection fraction than patients with a more normal left ventricular volume (≤75 mL/m 2 ). Conclusions Active myocarditis is associated with early left ventricular remodeling and the development of a spherical chamber. These changes correlate with ventricular dilatation and reduced left ventricular ejection fraction. (Am Heart J 1999;138:303-8.)

To assess the predictive value of right ventricular systolic function in patients with active myocarditis, the echocardiograms of 23 patients with biopsy-confirmed myocarditis were reviewed. Right ventricular systolic function was evaluated qualitatively and quantitatively by descent of the right ventricular base. Patients were divided into those with normal right ventricular function, in whom right ventricular descent was 1.9 +/- 0.1 cm, and those with abnormal right ventricular function, in whom right ventricular descent was 0.8 +/- 0.1 cm (p0.001). There were no differences between the two groups in age, duration of symptoms, baseline hemodynamics, or histologic assessment. Initial left ventricular ejection fraction was significantly lower in patients with depressed right ventricular function (27.5 +/- 4.9%) compared with that in patients with normal right ventricular function (47.5 +/- 6.3%) (p = 0.01). The likelihood of an adverse outcome, defined as death or need for cardiac transplantation, was greater in patients with abnormal right ventricular function (right ventricular descentor = 1.7 cm) than in patients with normal right ventricular function (right ventricular descent1.7 cm) (p0.03). Multivariate analysis revealed that right ventricular dysfunction as quantified by right ventricular descent was the most powerful predictor of adverse outcome.

Myocardial ischemia and infarction are known to cause changes in both ventricular shape and function. Little is known about the recovery of ventricular geometry after transient myocardial ischemia and its relationship to recovery of function. To examine the pattern of recovery of ventricular geometry following transient coronary artery occlusion and to assess the relationship of this to the return of systolic function, we used echocardiography to study 13 dogs following 15-minute occlusion of the left anterior descending coronary artery. During ischemia, total endocardial surface area (ESA) increased from 32.55 +/- 1.77 to 45.36 +/- 3.18 cm2 (p = 0.001). The most striking increase was at the apex, where circumference increased from 5.04 +/- 0.24 at baseline to 7.86 +/- 0.43 cm at the end of occlusion (p = 0.0001), an increase of 58%. During reperfusion, ventricular geometry rapidly returned toward normal (baseline), with recovery of 80% of the increase in ESA evident by 15 minutes of reperfusion. Recovery of systolic function was substantially slower (p < 0.005 for all periods of observation during the 2 hours of reperfusion). During reperfusion, recovery of ventricular geometry and function was not uniform throughout the ischemic bed. The apex recovered most slowly, with the centroid of the area of abnormal contraction progressively moving along the long axis of the left ventricle toward the apex. There was also a progressive decrease in the radius of the area of dysfunction, from 2.0 +/- 0.15 at end occlusion to 0.13 +/- 0.07 cm at 120 minutes of reperfusion (p = 0.0001). There was no difference in blood flow between the apical and anterior segments during ischemia or reperfusion. Reperfusion favorably reduced the ischemic zone dilation before recovery of active systolic function and geometric recovery thus may be important in determining ultimate functional recovery. In addition, recovery of function proceeded inward towards the center of the ischemic territory and in a wavefront from the base to apex. This heterogeneous and asymmetric recovery suggests that sampling at one point within the ischemic zone may not reflect the true temporal pattern of recovery.

Background Electrical cardioversion in patients with atrial fibrillation (AF) is associated with an increased risk of stroke. We compared a transesophageal echocardiography (TEE)–guided strategy with a conventional strategy in patients with AF >2 days' duration undergoing electrical cardioversion over a 6-month follow-up. Methods The ACUTE study was a multicenter, randomized, clinical trial, with 1222 patients. Six-month follow-up was available in 1034 patients (85%), 525 in the TEE group and 509 in the conventional group. The primary composite end points were cerebrovascular accident, transient ischemic attack, and peripheral embolism at 6 months, which was a prespecified time point. Secondary end points were hemorrhage, mortality, and sinus rhythm. Results At 6 months, there was no difference in composite embolic events between the TEE group and the conventional group (10 [2%] vs 4 [0.8%]; risk ratio (RR) 2.47, 95% CI 0.78-7.88; P = .11). However, the hemorrhagic rate was significantly lower in the TEE group (23 [4.4%] vs 38 [7.5%]; RR 0.58, 96% CI 0.35-0.97; P = .04). There was no difference between the 2 treatment groups in all-cause mortality (21 [4%] vs 14 [2.8%]; RR 1.48, 95% CI 0.76-2.92; P = .25) and in the occurrence of normal sinus rhythm between the 2 groups (305 [62.2%] vs 280 [58.1%]; P = .51). Sinus rhythm at 6 months was more common in the TEE-guided group, in those patients who had direct current cardioversion (238 [62.5%] vs 151 [53.9%]; P = .03). Conclusion The TEE-guided strategy may be considered a clinically effective alternative to a conventional anticoagulation strategy for patients with AF of >2 days' duration undergoing electrical cardioversion over a 6-month period.

Diastolic dysfunction is common immediately after coronary artery bypass surgery (CABG). The duration of this phenomenon is unknown. Intravenous calcium is frequently administered during separation from cardiopulmonary bypass (CPB). We sought to determine whether intravenous calcium influences perioperative diastolic function and whether diastolic dysfunction persists into the postoperative period.Patients undergoing first-time elective CABG (n = 29) were randomly assigned to receive intravenous calcium chloride (n = 13) or placebo (n = 16) during separation from CPB. Diastolic function was assessed by the pressure-area relation with transesophageal echocardiography and pulmonary capillary wedge pressure (PCWP) measured simultaneously. Left ventricular end-diastolic area (LVEDA) and Doppler indexes were measured at comparable PCWP (within 2 mm Hg) at baseline, after separation from CPB, after sternal closure, and 3 hours after surgery. After CABG, both groups had a significant decrease in LVEDA and mitral E-wave deceleration time that persisted at 3 hours. Because there were no significant differences between the calcium and control groups at any time point, the data for the entire study cohort was analyzed. The LVEDA decreased (stiffness increased) progressively from 16.9 +/- 3.4 cm2 at baseline to 15.8 +/- 2.9 cm2 after CPB, 14.9 +/- 2.5 cm2 after sternal closure, and 14.3 +/- 3.1 cm2 at 3 hours after surgery (P.0001). The mitral E-wave deceleration time measured at the same time points was 168 +/- 47 ms, 136 +/- 25 ms, 137 +/- 36 ms, and 111 +/- 44 ms (P =.0001).An increase in left ventricular diastolic chamber stiffness is nearly universal after CABG, and it persists for at least 3 hours after surgery. An intravenous bolus of calcium chloride given during separation from CPB has no measurable negative effect on diastolic function. In the setting of increased chamber stiffness, the PCWP alone does not adequately reflect the volume status and effective preload of the left ventricle.

To determine whether the increased prevalence of congestive heart failure in women compared with men undergoing diagnostic cardiac catheterization is the result of a difference in the left ventricular pressure/volume relation, we retrospectively compared the clinical characteristics, left ventricular ejection fraction, and end-diastolic pressure and volume in 586 women and 1081 men undergoing diagnostic coronary angiography and left ventriculography. In comparison with men, women were older (63 vs 60 years; p = 0.0001) and had more hypertension (41% vs 31%; p = 0.0001), diabetes (18% vs 12%; p = 0.003), and symptoms of congestive heart failure (13% vs 10%; p = 0.05). In spite of this, women had a better mean left ventricular ejection fraction (61% vs 56%; p = 0.0001) and less prevalent three-vessel disease (23% vs 34%; p = 0.0001). Left ventricular end-diastolic volume index was smaller in women compared with men (73 vs 79 ml/m2; p = 0.0001) in spite of having similar left ventricular end-diastolic pressure. When patients were stratified according to left ventricular end-diastolic pressure, women had a significantly smaller end-diastolic volume than men did when left ventricular end-diastolic pressure was > or = 18 mm Hg (74 vs 86 ml/m2; p = 0.0001). In a multivariate analysis, female sex remained an independent predictor of congestive heart failure (odds ratio 1.72, 95% confidence interval 1.11 to 2.66, p = 0.02). This study suggests that diastolic dysfunction is one mechanism for the paradox of more frequent heart failure symptoms in spite of better preserved left ventricular systolic function in women. Sex appears to influence the pattern of myocardial dysfunction in patients with known or suspected coronary artery disease, but the basis for this observation remains speculative.

Fig. 3. Atria1 extrastimulus study after administration of sotalol at BCL 700 msec. Upper panel, Normal conduction of premature beat with a Hz-V:! interval of 90 msec. Middle panel, As HI-HZ interval shortens by 10 msec to 505, premature beat is conducted with left BBB pattern and Hz-V2 of 100 msec. Lower panel, Further shortening of HI-HZ interval to 490 msec causes sudden jump of HY-VZ interval to 220 msec with right. BBB morphology of conducted beat.