Anders Roijer

Cerebral lesions on magnetic resonance imaging, heart disease, and vascular risk factors in subjects without stroke. A population-based study.

Background and Purpose To assess the prevalence of asymptomatic abnormalities on magnetic resonance imaging of the brain and their possible relation to hypertension, heart disease, and carotid artery disease, we studied 77 randomly selected subjects (mean age, 65.1 years; range, 36 to 95 years) with no history of focal brain lesions. Methods The study protocol included magnetic resonance imaging of the brain, transthoracic and transesophageal echocardiography, ultrasonography of the carotid arteries, and electrocardiographic recording. Deep and periventricular white matter hyperintensities on magnetic resonance imaging were assessed both separately and together. Results On magnetic resonance imaging of the brain 62.3% (95% confidence interval [CI], 51.5% to 73.2%) of the subjects had white matter hyperintensities. These abnormalities increased significantly with age (x2 test; P=.0001), from 13.6% (95% CI, 0% to 28.0%) of subjects aged younger than 55 years to 85.2% (95% CI, 71.8% to 98.6%) of subjects aged 75 years or older. Six subjects had deep gray matter hyperintensities localized in the basal ganglia, and one had a cerebellar infarction. Stepwise logistic regression analysis identified age and a history of heart disease (but not echocardiographic findings) to be independently associated with deep and periventricular white matter hyperintensities. Hypertension was only independently associated with periventricular white matter hyperintensities. Of the 68 subjects examined with both transthoracic and transesophageal echocardiography, potential cardioembolic sources were detected in 38.2% (95% CI, 26.7% to 49.8%) of the subjects with transthoracic echocardiography and in 47.1% (95% CI, 35.2% to 58.9%) of those with transthoracic and transesophageal echocardiography combined. In subjects aged 75 years or older, a possible cardiac embolic source was detected in 64.0% on transthoracic echocardiography and in 72.0% on transthoracic and transesophageal echocardiography combined, compared with 5.3% and 15.8%, respectively, in subjects aged younger than 55 years. Conclusions White matter hyperintensities and potential cardioembolic sources are frequently present in asymptomatic individuals, stressing the need for age-matched control subjects in studies of patients with stroke or dementia.

Carotid artery and heart disease in subtypes of cerebral infarction.

BACKGROUND AND PURPOSE The aim of the study was to determine the prevalences of carotid artery disease and major and minor potential cardioembolic sources (1) in patients with cerebral infarction and age-matched control subjects and (2) in different clinical subtypes of cerebral infarction. METHODS A series of 166 consecutive patients with cerebral infarction and 59 control subjects was examined. The study protocol included clinical subtyping of the cerebral infarctions, ultrasonography of the carotid arteries, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), ECG, and examination of the brain with computed tomography, magnetic resonance imaging, or autopsy. RESULTS Carotid artery stenosis > or = 80% or occlusion was present in 35 (21%) patients but in no control subjects (P < .001; chi 2 test). A major potential cardioembolic source was detected in 65 (39%) patients and 3 (5%) control subjects. Atrial fibrillation was present in 35 (21%) patients and 3 (5%) control subjects at initial ECG (P < .01) and in 47 (28%) patients at repeat examination; 17 patients had paroxysmal atrial fibrillation. Sinus rhythm and a major potential cardioembolic source were detected in 18 (11%) patients but in no control subjects (P < .01) at TTE (all patients and control subjects examined) or TEE (118 patients and 52 control subjects examined). The frequency of a minor potential cardioembolic source detectable at TTE or TEE was similar in the patient and control groups (51% and 53%, respectively [NS]) and increased significantly with age. A finding of carotid artery stenosis > or = 80% or occlusion, atrial fibrillation, or a major cardioembolic source detected at TTE or TEE was more frequent among patients with cortical symptoms from anterior or middle cerebral artery territories than among those with lacunar syndromes (66% versus 22%, respectively). The probable source of cerebral infarction was identified in most of the 166 patients: cardiac embolism in 28% of cases (n = 46), carotid artery disease in 8% (n = 14), both cardiac embolism and carotid artery disease in 7% (n = 11), and lacunar infarction in 23% (n = 38). In 57 (34%) of the patients no unequivocal cause of the cerebral infarction was found. CONCLUSIONS The prevalences of carotid artery and heart disease differ significantly between clinical subtypes of cerebral infarction. The cause of cerebral infarction remains uncertain in one third of patients. Because a minor potential cardioembolic source occurs in about 50% of both patients and control subjects, this finding is of questionable value as a risk factor for stroke in the elderly.

Manual correction of semi-automatic three-dimensional echocardiography is needed for right ventricular assessment in adults; validation with cardiac magnetic resonance

BackgroundThree-dimensional echocardiography (3DE) and semi-automatic right ventricular delineation has been proposed as an appropriate method for right ventricle (RV) evaluation. We aimed to examine how manual correction of semi-automatic delineation influences the accuracy of 3DE for RV volumes and function in a clinical adult setting using cardiac magnetic resonance (CMR) as the reference method. We also examined the feasibility of RV visualization with 3DE.Methods62 non-selected patients were examined with 3DE (Sonos 7500 and iE33) and with CMR (1.5T). Endocardial RV contours of 3DE-images were semi-automatically assessed and manually corrected in all patients. End-diastolic (EDV), end-systolic (ESV) volumes, stroke volume (SV) and ejection fraction (EF) were computed.Results53 patients (85%) had 3DE-images feasible for examination. Correlation coefficients and Bland Altman biases between 3DE with manual correction and CMR were r = 0.78, -22 ± 27 mL for EDV, r = 0.83, -7 ± 16 mL for ESV, r = 0.60, -12 ± 18 mL for SV and r = 0.60, -2 ± 8% for EF (p < 0.001 for all r-values). Without manual correction r-values were 0.77, 0.77, 0.70 and 0.49 for EDV, ESV, SV and EF, respectively (p < 0.001 for all r-values) and biases were larger for EDV, SV and EF (-32 ± 26 mL, -21 ± 15 mL and - 6 ± 9%, p ≤ 0.01 for all) compared to manual correction.ConclusionManual correction of the 3DE semi-automatic RV delineation decreases the bias and is needed for acceptable clinical accuracy. 3DE is highly feasible for visualizing the RV in an adult clinical setting.

Combined preoperative information using a bullseye plot from speckle tracking echocardiography, cardiac CT scan, and MRI scan: targeted left ventricular lead implantation in patients receiving cardiac resynchronization therapy

AIMS To evaluate the feasibility and incremental value of using an integrated bullseye model for presenting data from cardiac computed tomography (CT) and magnetic resonance imaging (MRI) in combination with echocardiography evaluation of segmental mechanical delay for guiding optimal left ventricular lead placement in cardiac resynchronization therapy (CRT). METHODS AND RESULTS Thirty-nine patients (69 ± 9.7 years, 77% male, 82% with LBBB, 54% with ischaemic cardiomyopathy, 82% New York Heart Association classification of heart failure III) eligible for CRT were included. The left ventricular segment with the latest mechanical activation was determined by echocardiography with speckle tracking radial strain. Cardiac CT scan was used for anatomical evaluation of the coronary sinus and its branches. Cardiac MRI was used for evaluation of viability. A composite bullseye plot was constructed, indicating the most appropriate site for left ventricle (LV) lead placement. The latest mechanical delay was in the basal-anterior (3%), basal-inferior (3%), basal-inferolateral (13%), basal-anterolateral (21%), mid-anterior (8%), mid-inferior (3%), mid-inferolateral (34%), and mid-anterolateral (16%) segment. There were on average 2.5 ± 0.8 veins of suitable sizes (≥1.5 mm in diameter). A preoperative combined bullseye plot indicated that in 53% of the patients, there was a matching vein in the segment with the latest mechanical delay. If immediately adjacent segments were included, an optimal placement was possible in 95% of the patients. At 6 months, there was a statistically significant reduction in the left ventricular end systolic volume and the left ventricular ejection fraction was improved (P < 0.01). CONCLUSION Presenting data from echocardiography, cardiac CT, and MRI in a combined bullseye plot is both feasible and convenient for indicating the most appropriate site for LV lead placement. An optimal electrode position can be suggested in almost all patients.

Influence of Prosthesis-Patient Mismatch on Diastolic Heart Failure After Aortic Valve Replacement

BACKGROUND Bioprostheses for supraannular placement have been developed to optimize the hemodynamic performance after aortic valve replacement. To evaluate the potential benefit of this design, we analyzed the influence of prosthesis-patient mismatch on diastolic function and left ventricular mass regression and evaluated the clinical performance of the Sorin Soprano and Medtronic Mosaic in the aortic position. METHODS A total of 372 patients underwent aortic valve replacement between July 2004 and February 2007, receiving either a Sorin Soprano (n = 235) or a Medtronic Mosaic (n = 137) prosthetic valve. Echocardiographic and clinical data were collected prospectively, and follow-up was performed in April 2007. Multivariate analyses were used to identify differences in hemodynamic performance, diastolic function, left ventricular mass regression, and predictors of impaired survival. Kaplan-Meier survival curves and log-rank tests were used to compare postoperative outcomes. RESULTS The 30-day mortality was 1.7% (4 of 235 patients) in the Sorin Soprano group and 2.9% (4 of 137 patients) in the Medtronic Mosaic group (p = 0.473). Neither prosthesis-patient mismatch nor type of prosthesis was a significant predictor of early or late mortality. Diastolic heart failure was a predictor of poor survival (p = 0.004); however, the recovery of diastolic function was not significantly influenced by prosthesis-patient mismatch. Neither moderate (indexed effective orifice area < 0.85 cm(2)/m(2)) nor severe (indexed effective orifice area < 0.65 cm(2)/m(2)) prosthesis-patient mismatch resulted in a significantly impaired left ventricular mass regression. CONCLUSIONS Prosthesis-patient mismatch was not an independent predictor of poor survival, impaired left ventricular mass regression, or recovery of diastolic function. The Sorin Soprano and the Medtronic Mosaic bioprostheses demonstrated comparable hemodynamic performance and excellent clinical outcome without signs of structural valve deterioration during follow-up.

Role of Echocardiography in Systemic Arterial Embolism: A Review with Recommendations

The ability of echocardiography to diagnose sources of embolism and the role of the examination in the prediction of thromboembolism are reviewed. In addition, the yield of transthoracic (TTE) and transoesophageal echocardiography (TEE) is analysed in patients with suspected embolism and guidelines are proposed for performing echocardiography in this setting. In general, echocardiography is reliable for diagnosing sources of embolism and this applies in particular to TEE in the case of atrial, valvular, and aortic abnormalities. However, the method is useful for predicting embolism in a few cases only. There is a substantial risk in the event of mobile or protruding thrombi, but screening for these and other markers of thromboembolism seems to be unproductive in most groups of risk patients. Yet, in the presence of atrial fibrillation, echocardiography may be helpful in defining patients with an otherwise normal heart and low risk of embolism--and in defining the relatively rare patient with a clinically low-risk profile but moderate-to-severe left ventricular systolic dysfunction and a high risk of embolism. TEE-guided conversion of atrial fibrillation without weeks of preceding anticoagulation may prove useful, after further investigation. The risk of embolism in relation to the size and mobility of valvular vegetations has remained controversial. In patients with suspected recent embolism, TTE results in less than 5% new therapeutic consequences. In those with a normal TTE, the yield of TEE seems to be equally low. We therefore recommend a selective strategy: TTE and TEE can be omitted when a cardiac source of embolism appears from the clinical setting and in most patients with an obvious predisposition to cerebrovascular disease. However, in the latter cases TTE should be performed if indicated by the clinical situation, e.g. in the presence of fever and murmur. TTE is also recommended when there are no obvious markers of primary vascular disease. To preclude very rare sources of embolism (e.g. atrial thrombi despite sinus rhythm), supplementary TEE is recommended in younger patients in whom primary vascular disease is very unlikely. The diagnosis by TEE of common conditions such as atrial septal aneurysms and patent foramen ovale cannot, however, be taken as proof of the mechanism of a systemic arterial occlusive event; thus it is difficult to change therapy on the basis of such diagnoses.

Prediction of sinus rhythm maintenance following DC-cardioversion of persistent atrial fibrillation – the role of atrial cycle length

BackgroundAtrial electrical remodeling has been shown to influence the outcome the outcome following cardioversion of atrial fibrillation (AF) in experimental studies.The aim of the present study was to find out whether a non-invasively measured atrial fibrillatory cycle length, alone or in combination with other non-invasive parameters, could predict sinus rhythm maintenance after cardioversion of AF.MethodsDominant atrial cycle length (DACL), a previously validated non-invasive index of atrial refractoriness, was measured from lead V1 and a unipolar oesophageal lead prior to cardioversion in 37 patients with persistent AF undergoing their first cardioversion.Results32 patients were successfully cardioverted to sinus rhythm. The mean DACL in the 22 patients who suffered recurrence of AF within 6 weeks was 152 ± 15 ms (V1) and 147 ± 14 ms (oesophagus) compared to 155 ± 17 ms (V1) and 151 ± 18 ms (oesophagus) in those maintaining sinus rhythm (NS). Left atrial diameter was 48 ± 4 mm and 44 ± 7 mm respectively (NS). The optimal parameter predicting maintenance of sinus rhythm after 6 weeks appeared to be the ratio of the lowest dominant atrial cycle length (oesophageal lead or V1) to left atrial diameter. This ratio was significantly higher in patients remaining in sinus rhythm (3.4 ± 0.6 vs. 3.1 ± 0.4 ms/mm respectively, p = 0.04).ConclusionIn this study neither an index of atrial refractory period nor left atrial diameter alone were predictors of AF recurrence within the 6 weeks of follow-up. The ratio of the two (combining electrophysiological and anatomical measurements) only slightly improve the identification of patients at high risk of recurrence of persistent AF. Consequently, other ways to asses electrical remodeling and / or other variables besides electrical remodeling are involved in determining the outcome following cardioversion.

Cardiac changes in stroke patients and controls evaluated with transoesophageal echocardiography

In stroke patients several cardiac changes associated with embolism can be detected with transoesophageal echocardiography. Potential major cardiac embolic sources (e.g. atrial fibrillation, thrombi of left ventricle/atrium, vegetation, myxoma, dilated cardiomyopathy) have a causal relationship to embolism. Other changes with no certain causal relationship are regarded as potential minor cardiac embolic sources (e.g. atrial septal aneurysm, patent foramen ovale, mitral annular calcification, mitral valve prolapse, protruding atheroma of the aorta). We compared the prevalences of major and minor potential cardiac embolic sources in a stroke population with that in controls. One hundred and twenty-one patients with first-ever stroke were compared with 68 randomly selected controls. All subjects underwent magnetic resonance imaging of the brain, carotid ultrasound and transthoracic/transoesophageal echocardiography. The patients were slightly older (mean age 70.7 +/- 10.3 years) than the controls (65.5 +/- 15.5 years) (p < 0.05). Potential major cardiac embolic sources were found in 27% of the patients and in 4% of the controls (p < 0.001). The most common major potential embolic source was atrial fibrillation, detected in 22/121 patients. Fifteen of these also had spontaneous echocontrast in the left atrium. Eleven left atrial thrombi were found (four of these patients had atrial fibrillation and seven had sinus rhythm). A history of heart disease was more common in patients with a potential major cardiac embolic source or a carotid artery stenosis (77%) than in those patients without (44%) (p < 0.01). After excluding subjects with a major potential cardiac embolic source and/or carotid artery stenosis, no differences in the prevalence of minor potential cardiac embolic sources were found between patients (55%) and control subjects (47%) (p = NS). Even when subjects without a major potential cardiac embolic source or a carotid artery stenosis were categorized into three age groups (35-54, 55-74 and > 74 years) the prevalence of potential minor cardiac embolic sources did not differ between patients and controls. To conclude, major potential cardiac embolic sources are more common in an older population with first-ever stroke than in a comparable control group. However, potential minor cardiac embolic sources did not differ in prevalence in the patients compared with controls. Certain changes (e.g. atrial septal aneurysm) might have a potential embolic role in younger stroke patients but in our study no difference was found between older stroke patients and controls.

Low atrial fibrillatory rate is associated with spontaneous conversion of recent-onset atrial fibrillation.

AIMS Atrial fibrillatory rate (AFR) is considered a non-invasive index of atrial remodelling. Low AFR has been associated with favourable outcome of interventions in patients with persistent atrial fibrillation (AF). However, AFR has never been studied in unselected patients with short duration of AF, prone to regain sinus rhythm (SR) spontaneously. The aim of the study was to assess if AFR can predict spontaneous conversion in patients with recent-onset AF. METHODS AND RESULTS Files of consecutive patients with AF < 48 h seeking emergency room care during a 12-month period were screened (n = 225). Patients with thyroid illness, acute ischaemic heart disease (IHD) or acute congestive heart failure, significant valvular heart disease, congenital heart disease, history of cardiac surgery or catheter ablation, or on class I/III antiarrhythmics were excluded. Atrial fibrillatory rate was obtained by QRST cancellation and time frequency analysis of electrocardiogram at admission. The study population comprised 148 patients (age 64 ± 13 years, 52 men), of whom 48 converted to SR within 18 h. Those converting spontaneously comprised more women, had a higher prevalence of first-ever AF episode, IHD, and a lower AFR. The multivariate analysis revealed: AFR < 350 fibrillations per minute [odds ratio (OR) 3.7, 95% confidence interval (CI) 1.3-10.5, P = 0.016], IHD (OR 5.7, 95% CI 1.5-22.4, P = 0.012) and first-ever AF episode (OR 4.1, 95% CI 1.3-13.0, P = 0.015) as independent predictors of spontaneous conversion. CONCLUSION A low AFR was predictive of spontaneous conversion in patients with recent-onset AF. Along with first-ever AF episode and IHD, AFR can be used in assessing likelihood of spontaneous conversion, if proven in prospective studies.

A new de-airing technique that reduces systemic microemboli during open surgery: a prospective controlled study.

OBJECTIVE We have evaluated a new technique of cardiac de-airing that is aimed at a) minimizing air from entering into the pulmonary veins by opening both pleurae and allowing lungs to collapse and b) flushing out residual air from the lungs by staged cardiac filling and lung ventilation. These air emboli are usually trapped in the pulmonary veins and may lead to ventricular dysfunction, life-threatening arrhythmias, and transient or permanent neurologic deficits. METHODS Twenty patients undergoing elective true left open surgery were prospectively and alternately enrolled in the study to the conventional de-airing technique (pleural cavities unopened, dead space ventilation during cardiopulmonary bypass [control group]) and the new de-airing technique (pleural cavities open, ventilator disconnected during cardiopulmonary bypass, staged perfusion, and ventilation of lungs during de-airing [study group]). Transesophageal echocardiography and transcranial Doppler continually monitored the air emboli during the de-airing period and for 10 minutes after termination of the cardiopulmonary bypass. RESULTS The amount of air embolism as observed on echocardiography and the number of microembolic signals as recorded by transcranial Doppler were significantly less in the study group during the de-airing time (P < .001) and the first 10 minutes after termination of cardiopulmonary bypass (P < .001). Further, the de-airing time was significantly shorter in the study group (10 vs 17 minutes, P < .001). CONCLUSION The de-airing technique evaluated in this study is simple, reproducible, controlled, safe, and effective. Moreover, it is cost-effective because the de-airing time is short and no extra expenses are involved.