Seward, James B.

Background— Limited data exist on trends in incidence of atrial fibrillation (AF). We assessed the community-based trends in AF incidence for 1980 to 2000 and provided prevalence projections to 2050. Methods and Results— The adult residents of Olmsted County, Minnesota, who had ECG-confirmed first AF in the period 1980 to 2000 (n=4618) were identified. Trends in age-adjusted incidence were determined and used to construct model-based prevalence estimates. The age- and sex-adjusted incidence of AF per 1000 person-years was 3.04 (95% CI, 2.78 to 3.31) in 1980 and 3.68 (95% CI, 3.42 to 3.95) in 2000. According to Poisson regression with adjustment for age and sex, incidence of AF increased significantly ( P =0.014), with a relative increase of 12.6% (95% CI, 2.1 to 23.1) over 21 years. The increase in age-adjusted AF incidence did not differ between men and women ( P =0.84). According to the US population projections by the US Census Bureau, the number of persons with AF is projected to be 12.1 million by 2050, assuming no further increase in age-adjusted incidence of AF, but 15.9 million if the increase in incidence continues. Conclusions— The age-adjusted incidence of AF increased significantly in Olmsted County during 1980 to 2000. Whether or not this rate of increase continues, the projected number of persons with AF for the United States will exceed 10 million by 2050, underscoring the urgent need for primary prevention strategies against AF development.

Background and Purpose— With the changes in management of atrial fibrillation (AF) over time, it is possible that the time trends of post-AF stroke incidence and mortality have changed. We sought to determine whether the incidence and survival of ischemic stroke after AF diagnosis have improved. Methods— We identified the Olmsted County, Minn, residents who developed first AF from 1980 to 2000 and followed them in medical records to 2004. The outcomes were first ischemic stroke and death. Results— Of the 4117 subjects diagnosed with first AF and without previous stroke, 446 (11%) sustained a first ischemic stroke during a mean follow-up time of 5.5±5.0 years. The age- and sex-adjusted incidence of stroke decreased, on average, by 3.4% per year ( P =0.0001), concurrent with an increase in warfarin and aspirin use (both P <0.0001) and reduction of systolic blood pressure ( P <0.001). The age-adjusted ischemic stroke incidence was higher in women ( P =0.039), but not after adjusting for systolic blood pressure ( P =0.41). Compared with the general Minnesota white population, the relative mortality hazard ratio was 1.88 for men and 1.84 for women without stroke and 3.03 for men and 3.80 for women ( P <0.05) with stroke. The relative mortality hazard did not vary by age or calendar year of AF diagnosis. Conclusions— Post-AF ischemic stroke incidence decreased significantly from 1980 to 2000, during which time a substantial increase in the use of antithrombotic therapy and reduction of systolic blood pressure was evident. The relative mortality risk of stroke, however, had not improved over time.

Background— Sinus venosus atrial septal defect (SVASD) differs from secundum atrial septal defect by its atrial septal location and its association with anomalous pulmonary venous connection (APVC). Data on long-term outcome after surgical repair are limited. Methods and Results— We reviewed outcomes of 115 patients (mean age±SD 34±23 years) with SVASD who had repair from 1972 through 1996. APVC was present in 112 patients (97%). Early mortality was 0.9%. Complete follow-up was obtained for 108 patients (95%) at 144±99 months. Symptomatic improvement was noted in 83 patients (77%), and deterioration was noted in 17 patients (16%). At follow-up, 7 (6%) of 108 patients had sinus node dysfunction, a permanent pacemaker, or both, and 15 (14%) of 108 patients had atrial fibrillation. Older age at repair was predictive of postoperative atrial fibrillation ( P =0.033). No reoperations were required during follow-up. Survival was not different from expected for an age- and sex-matched population. Clinical improvement was more common with older age at surgery ( P =0.014). Older age at repair ( P =0.008) and preoperative New York Heart Association class III or IV ( P =0.038) were independent predictors of late mortality. Conclusions— Operation for SVASD is associated with low morbidity and mortality, and postoperative subjective clinical improvement occurs irrespective of age at surgery. Postoperative atrial fibrillation appears to be related to older age at operation. SVASD repair achieves survival similar to that of a matched population and should be considered whenever repair may impact survival or symptoms.

Background— In this study we evaluate the diastolic deformation of ischemic/reperfused myocardium and relate this deformation to tissue elastic properties. Methods and Results— Farm pigs were subjected to left anterior descending coronary artery occlusion followed by reperfusion to create either stunning (n=12) or transmural myocardial infarction (n=12). Ultrasound-derived radial strain rates (SR) and strain were measured in the ischemic and remote walls. Myocardial stiffness was estimated from diastolic pressure–wall thickness relationship obtained from preload alterations. At reperfusion, end-systolic strain (ε sys ) was significantly reduced in both stunned and infarcted walls compared with their remote walls (3±3% versus 26±2% and 1±0% versus 33±5%, respectively; P <0.0001) or baseline values. Diastolic passive deformation (ε A ) and rates of deformation during early (E SR ) and late (A SR ) diastole were comparable between stunned and remote walls (ε A : 7.3±1.6% versus 7.9±1.9%; E SR : −2.7±0.4 s −1 versus −2.6±0.5 s −1 ; A SR : −1.8±0.2 s −1 versus −1.9±0.3 s −1 ; P =NS for all) but were of significantly lower magnitude in infarcted walls versus remote walls (ε A : 1.1±0.2% versus 11.4±1.9%; E SR : −0.3±0.1 s −1 versus −2.4±0.4 s −1 ; A SR : −0.3±0.1 s −1 versus −2.5±0.4 s −1 ; P <0.0001 for all). Stiffness coefficient of exponential diastolic pressure–wall thickness relation was higher for infarcted ( P <0.05) but not for stunned walls ( P =NS) compared with their remote walls. Conclusions— Early after postischemic reperfusion and in the presence of severely reduced systolic deformation, diastolic passive deformation (and rates of deformation) can distinguish stiff, noncompliant, transmurally infarcted myocardial walls from those more compliant walls containing viable but stunned myocardium.

Background— After acute myocardial infarction (AMI), diastolic function assessed by Doppler echocardiography provides important prognostic information that is incremental to systolic function. However, Doppler variables are affected by multiple factors and may change rapidly. In contrast, left atrial (LA) volume is less influenced by acute changes and reflects subacute or chronic diastolic function. This may be of importance when one assesses risk in patients with AMI. Methods and Results— Three hundred fourteen patients with AMI who had a transthoracic echocardiogram with assessment of left ventricular (LV) systolic and diastolic function and measurement of LA volume during admission were identified. The LA volume was corrected for body surface area, and the population was divided according to LA volume index of 32 mL/m 2 (2 SDs above normal). LA volume index was >32 mL/m 2 in 142 (45%). The primary study end point was all-cause mortality. During follow-up of 15 (range 0 to 33) months, 46 patients (15%) died. LA volume index was a powerful predictor of mortality and remained an independent predictor (hazard ratio 1.05 per 1-mL/m 2 change, 95% CI 1.03 to 1.06, P <0.001) after adjustment for clinical factors, LV systolic function, and Doppler-derived parameters of diastolic function. Conclusions— Increased LA volume index is a powerful predictor of mortality after AMI and provides prognostic information incremental to clinical data and conventional measures of LV systolic and diastolic function.

Background — Left atrial (LA) thrombus is infrequently detected in the presence of sinus rhythm (SR) and, in these cases, is usually associated with additional cardiac pathologies. We sought to determine the clinical and echocardiographic characteristics of patients with LA thrombus and SR to define a high-risk group of patients prone to this uncommon clinical presentation. Methods and Results — The institution’s echocardiographic laboratory database was searched to identify patients with LA thrombus, diagnosed by transesophageal echocardiography (TEE), who were in SR during the TEE examination. Of 20 643 consecutive TEE examinations performed during an 11-year period, LA thrombus was detected in 314 patients in 380 TEE examinations. Of these, SR was present in 20 patients (age 69±13 years; 40% men) in 23 examinations (0.1% of all TEE examinations; 6.1% of TEE examinations with LA thrombus). High-risk structural heart disease (severe left ventricular dysfunction or significant left-sided valve disease [predominantly mitral valve disease]), previous documented episodes of atrial fibrillation, or both (structural heart disease and previous atrial fibrillation) were present in 10, 4, and 5 of the 20 patients, respectively. Only 1 patient with LA thrombus and SR did not have high-risk features. Conclusions — LA thrombus is very infrequently detected in the presence of SR. Patients with LA thrombus and SR constitute a high-risk group characterized by specific structural cardiac abnormalities or previous atrial fibrillation, abnormalities that are potentially detectable before TEE.

Background — Regional myocardial function assessment is essential in the management of coronary artery disease (CAD). Tissue Doppler imaging (TDI) by depicting local myocardial motion can potentially quantify regional myocardial function. Strain rate imaging (SRI) that depicts regional deformation is less susceptible to cardiac translation and tethering and may be superior to TDI for regional function analysis. We examined regional myocardial function using TDI and SRI in a unique clinical model of a small, discrete myocardial infarction. Method and Results — Ten patients with severely symptomatic septal hypertrophy underwent basal septal ablation via intracoronary alcohol injection and had TDI and SRI pre- and postablation. Invasive hemodynamics showed no appreciable change in global function. Peak systolic strain rate was significantly lower postablation versus preablation (−0.5 versus −1.2 s −1 , P <0.001) and when comparing infarct and noninfarct areas (−0.5 versus −1.5 s −1 , P <0.001). In contrast, peak systolic tissue velocities were similar pre- and postablation (3.9 versus 2.9 cm/s, P =0.16) and between infarct and noninfarct areas (2.9 versus 2.2 cm/s, P =0.13). SRI analysis demonstrated reduced systolic function in the peri-infarct zone and preserved systolic function in the remote nonischemic zone. Conclusion — In the clinical setting of a small, discrete infarct unaccompanied by changes in global function, SRI accurately depicted changes in regional function. These data suggest that SRI may be the optimal method for objective, quantitative assessment of regional myocardial dysfunction.