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BACKGROUND The post cardiac arrest syndrome (PCAS) is responsible for the majority of in-hospital deaths following cardiac arrest (CA). The major elements of PCAS are anoxic brain injury and circulatory failure. OBJECTIVE This study aimed to investigate the clinical characteristics of circulatory failure and inflammatory responses after out-of-hospital cardiac arrest (OHCA) and to identify patterns of circulatory and inflammatory responses, which may predict circulatory deterioration in PCAS. METHODS This study is a single-center cohort study of 50 patients who receive intensive care after OHCA. The patients are followed for 5 days where detailed information from circulatory variables, including measurements by pulmonary artery catheters (PACs), is obtained in high resolution. Blood samples for inflammatory and endothelial biomarkers are taken at inclusion and thereafter daily. Every 10 min, the patients will be assessed and categorized in one of three circulatory categories. These categories are based on mean arterial pressure; heart rate; serum lactate concentrations; superior vena cava oxygen saturation; and need for fluid, vasoactive medications, and other interventions. We will analyze predictors of circulatory failure and their relation to inflammatory biomarkers. RESULTS Patient inclusion started in January 2016. CONCLUSIONS This study will obtain advanced hemodynamic data with high resolution during the acute phase of PCAS and will analyze the details in circulatory state transitions related to circulatory failure. We aim to identify early predictors of circulatory deterioration and favorable outcome after CA. CLINICALTRIAL ClinicalTrials.gov: NCT02648061; https://clinicaltrials.gov/ct2/show/NCT02648061 (Archived by WebCite at http://www.webcitation.org/6wVASuOla)

Regional strain rate in the left ventricle can be assessed in real time and color mapped. The method is termed strain rate imaging (SRI), and findings correspond well with 2-dimensional echocardiography. This study addresses SRI as a method for localizing coronary lesions, compared with standard echocardiography. Twenty patients with acute myocardial infarction who underwent coronary angiography for clinical reasons were examined with SRI and standard echocardiography. Wall motion was graded by SRI color and separately by wall thickening. Strain rate imaging and 2-dimensional echocardiography results agreed well. An infarct-related artery was identified from angiograms combined with electrocardiograms. Both methods identified an infarct-related artery in 19 possible cases and had equal sensitivity and specificity for wall segments affected by lesion. Combining the information from both methods did not change accuracy. The study validates SRI as a method for assessing regional wall function in coronary artery disease. The advantages of SRI are discussed and measurements of strain rates are given.

We have developed a method for semiautomatic contour detection in M-mode images. The method combines tissue Doppler and grey-scale data. It was used to detect: 1. the left endocardium of the septum, the endocardium and epicardium of the posterior wall in 16 left ventricular short-axis M-modes, and 2. the mitral ring in 38 anatomical M-modes extracted pair-wise in 19 apical four-chamber cine-loops (healthy subjects). We validated the results by comparing the computer-generated contours with contours manually outlined by four echocardiographers. For all boundaries, the average distance between the computer-generated contours and the manual outlines was smaller than the average distance between the manual outlines. We also calculated left ventricular wall thickness and diameter at end-diastole and end-systole and lateral and septal mitral ring excursions, and found, on average, clinically negligible differences between the computer-generated indices and the same indices based on manual outlines (0.8-1.8 mm). The results were also within published normal values. In conclusion, this initial study showed that it was feasible in a robust and efficient manner to detect continuous wall boundaries in M-mode images so that tracings of left ventricular wall thickness, diameter and long axis could be derived.

This study assessed interobserver and intraobserver variation and diagnostic accuracy during 25 dipyridamole stress echocardiography tests interpreted with different analysis systems: a) computer display of high frame rate digital cineloops (47 frames/s); b) computer display of lower frame rate digital cineloops (24 frames/s); and c) videotape recordings. The majority of the patients (84%) had documented coronary artery disease with baseline wall motion anormalities due to previous myocardial infarctions and/or coronary bypass surgery, thus comprising a population with difficult interpretation of stress echocardiography. Diagnostic accuracy was assessed using coronary angiography as reference method. Interobserver and intraobserver agreement was highest when analysis was performed from computer-displayed cineloops, 96 and 92%, respectively, compared to 84 and 80% respectively, using videotape recordings. Sensitivity for identification of coronary artery stenosis was similar using digital cineloops with high frame rate or videotape recordings (67% to 80% for both systems), and tended to be lower using cineloops with lower frame rate for analysis (53%). Inter- and intraobserver differences for wall motion score index were not significantly influenced by the analysis system. We conclude that computer assisted analysis with high frame rate of the displayed cineloops provides optimal observer agreement and diagnostic accuracy in the same range as videotape analysis in patients undergoing stress echocardiography.

Calcitonin gene-related peptide (CGRP) is a neuropeptide co-stored with tachykinins (substance P, neurokinin A) in cerebrovascular sensory fibers in the trigeminal ganglion. Preceding studies on subarachnoid hemorrhage (SAH) revealed that an enhanced release of CGRP resulted in the selective loss of perivascular CGRP. Therefore, the present study was designed to evaluate the effects of intravenous administration of human alpha-CGRP on cerebral vasoconstriction in the postoperative course after SAH in 5 patients (8 infusions). Cerebral vasoconstriction was evaluated with transcranial Doppler sonography. The increase in the relationship between middle cerebral artery (MCA) velocity and internal carotid artery (ICA) velocity (the hemodynamic index) was used as an indicator of vasoconstriction and compared to the contralateral side. A significant reduction was found in the hemodynamic index during the CGRP infusion (4.3 +/- 0.5, P < 0.05) as to compared to before infusion (6.2 +/- 0.5). There was no measurable change in the hemodynamic index on the contralateral side. No significant change was observed in pulsatility index, blood pressure or consciousness during the peptide infusion. A significant increase in heart rate was observed during the infusion as compared to before and after infusion (90 +/- 4 vs. 76 +/- 5). Cardiac ultrasound data indicated a mean cardiac output increase of 1.9 liter/min, and a mean decrease in total peripheral resistance of 538 dynes s/cm5. The results obtained show that infusion of human alpha-CGRP may induce normalisation of cerebrovascular tone in SAH.

In stress echocardiography, ischaemia is detected as wall motion abnormalities. The test can be done both with exercise (which is the more sensitive) and pharmacological stress (which is more specific).The paper gives an overview of the method, of diagnostic and prognostic value as well as indications and contraindications, based on present literature.The sensitivity is 80-90%, specificity 75-100%, dependent on the extent and degree of disease. A negative test predicts a low cardiac event rate of about 1% per year and a low preoperative cardiac risk. The diagnostic accuracy is dependent on optimal equipment quality and on the experience of the examiner. Without specific training, sensitivity is about the same as with exercise ECG. The complication rate is low, dependent on the type of stress. Stress echocardiography is useful in patients unable to exercise, in preoperative risk assessment and in suspected false-negative exercise ECG. In addition it is a supplement to coronary angiography for evaluation of the significance of intermediate stenoses, to identify culprit lesion and for viability detection. Finally, it is useful in aortic stenosis with reduced left ventricular function for evaluation of stenosis and contractile reserve.

BACKGROUND: Regional strain rate in the left ventricle can be assessed by tissue Doppler velocity gradient and color mapped in real time. Regional contractility thus can be visualized and graded. To validate the method, we made a comparison with standard echocardiography. METHODS AND RESULTS: Fifteen patients with recent myocardial infarction were examined with the use of strain rate imaging (SRI). Velocity gradients were mapped by color. Gray-scale imaging was performed using the second harmonic mode. Cine loops of two-dimensional echocardiography (2-D echo) and SRI images from three standard apical planes were analyzed off line. A four-grade scale in 16 segments was used to score wall motion by 2-D echo and by SRI. Of a total of 236 segments, 235 segments were analyzable by 2-D echo and 218 segments were analyzable by SRI. Correlation of wall motion score index with ejection fraction was - 0.84 by 2-D echo and - 0.92 by SRI. One hundred fourteen segments had an equal score by the two methods: 51 segments differed by 1 degree and 14 segments differed by 2 degrees (kappa = 0.45). CONCLUSIONS: SRI agrees well with echocardiography in grading regional wall function, and the method can be seen as validated in a clinical setting for assessment of regional systolic wall function and is demonstrated to be applicable for semiquantitative wall motion assessment. SRI has theoretical advantages and may be a valuable addition to standard echocardiography, especially in the field of stress echocardiography.

Eighty-six patients, mean age 29 ± 15 years, underwent aortic valve reconstruction with bovine or autologous pericardial tissue. Mean clinical follow-up was 35 months. Echocardiographic data were assessed in 65 patients with follow-up ≥6 months. There were two in-hospital and three late deaths. Warfarin was not given, and no thromboembolic events occurred. Five (6%) patients needed reoperation because of severe aortic regurgitation. Peak aortic valve gradients remained low (26 ± 14 mm Hg for the bovine group and 16 ± 16 mm Hg for the autologous group). One patient is awaiting surgery for aortic stenosis after 76 months. Leaflet thickening at latest follow-up was marked in six (9%) patients. Left ventricular dimensions normalized postoperatively and showed only insignificant increase during follow-up. This technique is a promising alternative to valve prosthesis in selected patients; however, longer follow-up is necessary to assess long-term results.

Systemic arterial properties and left ventricular function were assessed by Doppler echocardiography and a calibrated subclavian artery pulse tracing early (5 weeks) and late (27 months) after a first acute myocardial infarction in 19 patients aged 44-77 years and in healthy subjects matched for age, gender, and arterial blood pressure. Total arterial compliance (3-element windkessel model) was reduced by 26% (p < 0.001) from early to late assessment, and left-ventricular end-diastolic and end-systolic volumes were increased by 11 and 18%, respectively (p < 0.05). Peripheral resistance and characteristic impedance were not significantly changed. The healthy matched subjects had arterial compliance similar to patients at early assessment, but tended to be higher at late. Thus, 2.3 years after a first acute myocardial infarction with moderate left ventricular dilatation, arterial distensibility was significantly decreased whereas peripheral resistance was not changed.

Diagnostic accuracy of high dose dipyridamole stress echocardiography (0.84 mg i.v./kg) for detecting coronary artery stenosis was assessed in 94 patients undergoing coronary angiography, and adverse effects were registered in the total study population of 120 patients. Echocardiographic analysis was performed with digital systolic cineloops with high frame-rate (47 frames/sec) for optimal left ventricular wall motion display. Results showed sensitivity of 73% for detection of arterial luminal stenosis > or = 75% or retrograde collateral flow to an occluded coronary artery. Sensitivity for detection of 1-vessel stenosis was 43% (6 of 14 patients), and for 2- and 3-vessel disease 79% (19 of 24) and 88% (16 of 18), respectively. Specificity was 92% (35 of 38), diagnostic accuracy 81%. The stenosed coronary artery was correctly localized in 85% of positive tests. Dipyridamole-induced increase in wall motion score index differed significantly between patients with 1-, 2-, and 3-vessel disease (0.02 +/- 0.17, 0.15 +/- 0.17, and 0.27 +/- 0.24, respectively), and early positive tests (dipyridamole dose of 0.56 mg/kg) were almost exclusively seen in patients with multivessel disease. Six patients (5%) developed symptomatic bradycardia and hypotension during the test. In conclusion, dipyridamole stress echocardiography is useful for detection and localization of coronary artery stenosis, particularly in patients with multivessel disease.

This study compared the diagnostic accuracy of dipyridamole (0.84 mg i.v./ 10 min) and bicycle stress echocardiography in 37 patients with inconclusive standard bicycle electrocardiography (ECG) tests; all underwent coronary angiography. Sensitivity for detection of coronary stenosis with dipyridamole echocardiography was 68% (21 of 31 patients), and for 1-, 2- and 3-vessel disease 56, 69 and 83%, respectively. Overall bicycle echocardiography sensitivity was 84%, and 78, 88 and 83% for patients with 1-, 2- and 3-vessel disease, respectively. Dipyridamole echocardiography was negative in all 6 patients with negative coronary angiography (specificity 100%), bicycle echocardiography was positive in 2 (specificity 67%). We conclude that dipyridamole echocardiography tends to be less sensitive in patients with mild disease, but is more specific than bicycle echocardiography.