AimsLeft ventricular (LV) pressure–strain loop area reflects regional myocardial work and metabolic demand, but the clinical use of this index is limited by the need for invasive pressure. In this study, we introduce a non-invasive method to measure LV pressure–strain loop area.Methods and resultsLeft ventricular pressure was estimated by utilizing the profile of an empiric, normalized reference curve which was adjusted according to the duration of LV isovolumic and ejection phases, as defined by timing of aortic and mitral valve events by echocardiography. Absolute LV systolic pressure was set equal to arterial pressure measured invasively in dogs (n = 12) and non-invasively in patients (n = 18). In six patients, myocardial glucose metabolism was measured by positron emission tomography (PET). First, we studied anaesthetized dogs and observed an excellent correlation (r = 0.96) and a good agreement between estimated LV pressure–strain loop area and loop area by LV micromanometer and sonomicrometry. Secondly, we validated the method in patients with various cardiac disorders, including LV dyssynchrony, and confirmed an excellent correlation (r = 0.99) and a good agreement between pressure–strain loop areas using non-invasive and invasive LV pressure. Non-invasive pressure–strain loop area reflected work when incorporating changes in local LV geometry (r = 0.97) and showed a strong correlation with regional myocardial glucose metabolism by PET (r = 0.81).ConclusionsThe novel non-invasive method for regional LV pressure–strain loop area corresponded well with invasive measurements and with directly measured myocardial work and it reflected myocardial metabolism. This method for assessment of regional work may be of clinical interest for several patients groups, including LV dyssynchrony and ischaemia.
Aims The EURO-ENDO registry aimed to study the management and outcomes of patients with infective endocarditis (IE). Methods and results Prospective cohort of 3116 adult patients (2470 from Europe, 646 from non-ESC countries), admitted to 156 hospitals in 40 countries between January 2016 and March 2018 with a diagnosis of IE based on ESC 2015 diagnostic criteria. Clinical, biological, microbiological, and imaging [echocardiography, computed tomography (CT) scan, 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT)] data were collected. Infective endocarditis was native (NVE) in 1764 (56.6%) patients, prosthetic (PVIE) in 939 (30.1%), and device-related (CDRIE) in 308 (9.9%). Infective endocarditis was community-acquired in 2046 (65.66%) patients. Microorganisms involved were staphylococci in 1085 (44.1%) patients, oral streptococci in 304 (12.3%), enterococci in 390 (15.8%), and Streptococcus gallolyticus in 162 (6.6%). 18F-fluorodeoxyglucose positron emission tomography/computed tomography was performed in 518 (16.6%) patients and presented with cardiac uptake (major criterion) in 222 (42.9%) patients, with a better sensitivity in PVIE (66.8%) than in NVE (28.0%) and CDRIE (16.3%). Embolic events occurred in 20.6% of patients, and were significantly associated with tricuspid or pulmonary IE, presence of a vegetation and Staphylococcus aureus IE. According to ESC guidelines, cardiac surgery was indicated in 2160 (69.3%) patients, but finally performed in only 1596 (73.9%) of them. In-hospital death occurred in 532 (17.1%) patients and was more frequent in PVIE. Independent predictors of mortality were Charlson index, creatinine > 2 mg/dL, congestive heart failure, vegetation length > 10 mm, cerebral complications, abscess, and failure to undertake surgery when indicated. Conclusion Infective endocarditis is still a life-threatening disease with frequent lethal outcome despite profound changes in its clinical, microbiological, imaging, and therapeutic profiles.
-There is a need for better methods to quantify regional myocardial function. In the present study, we investigated the feasibility of quantifying regional function in terms of a segmental myocardial work index as derived from strain Doppler echocardiography (SDE) and invasive pressure. In 10 anesthetized dogs, we measured left ventricular (LV) pressure by micromanometer and myocardial longitudinal strains by SDE and sonomicrometry. The regional myocardial work index (RMWI) was calculated as the area of the pressure-strain loop. As a reference method for strain, we used sonomicrometry. By convention, the loop area was assigned a positive sign when the pressure-strain coordinates rotated counterclockwise. Measurements were done at baseline and during volume loading and left anterior descending coronary artery (LAD) occlusion, respectively. There was a good correlation between RMWI calculated from strain by SDE and strain by sonomicrometry (y ϭ 0.73x ϩ 0.21, r ϭ 0.82, P Ͻ 0.01). Volume loading caused an increase in RMWI from 1.3 Ϯ 0.2 to 2.2 Ϯ 0.1 kJ/m 3 (P Ͻ 0.05) by SDE and from 1.5 Ϯ 0.3 to 2.7 Ϯ 0.3 kJ/m 3 (P ϭ 0.066) by sonomicrometry. Short-term ischemia (1 min) caused a decrease in RMWI from 1.3 Ϯ 0.2 to 0.3 Ϯ 0.04 kJ/m 3 (P Ͻ 0.05) and from 1.3 Ϯ 0.3 to 0.5 Ϯ 0.2 kJ/m 3 (P Ͻ 0.05) by SDE and sonomicrometry, respectively. In the nonischemic ventricle and during short-term ischemia, the pressure-strain loops rotated counterclockwise, consistent with actively contracting segments. Long-term ischemia (3 h), however, caused the pressure-strain loop to rotate clockwise, consistent with entirely passive segments, and the loop areas became negative, Ϫ0.2 Ϯ 0.1 and Ϫ0.1 Ϯ 0.03 kJ/m 3 (P Ͻ 0.05) by SDE and sonomicrometry, respectively. A RMWI can be estimated by SDE in combination with LV pressure. Furthermore, the orientation of the loop can be used to assess whether the segment is active or passive.sonomicrometry; pressure-strain loop STRAIN DOPPLER ECHOCARDIOGRAPHY (SDE) has been introduced as a new clinical method to measure regional myocardial function (2, 5, 18). As a measure of systolic function, one may use peak systolic strain, recorded either in the LV long axis as shortening strain or in the short axis as thickening strain. However, peak systolic strain is load dependant and therefore may not reflect systolic function when there are changes in loading conditions (18). This is analogous to the problem with load dependency of LV ejection fraction. In the latter case, one may use LV pressure-volume relations to differentiate between load-induced changes in function and changes in intrinsic myocardial contractility. Assessment of regional pressure-dimension loops, however, has not been feasible in clinical studies. In animal models, however, one may analyze regional function from pressure-segment length loops obtained from micromanometers and implanted sonomicrometric crystals (1,3,7,10,14,15,17). Similar to sonomicrometry, SDE provides a continuous measure of changes in regional dimension, and regional press...
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