Motion of the left ventricular left ventricle (LV) atrioventricular (AV) plane has been used to assess systolic LV function. The method has not been used properly to assess diastolic function, ...especially after a first myocardial infarction (MI). The diastolic function was assessed in 47 previously healthy patients with a first MI assessed by echocardiographic diastolic motion of the LV AV plane. The motion of the AV plane was recorded at four different LV sites, that is, at the septal, anterior, lateral, and inferior walls. Two distinct phases of motion were noticed during diastole at all the sites: one at the early diastole caused by rapid filling of the LV and the other at late diastole during the atrial contraction. The contribution of left atrial contraction to LV filling at different LV sites was calculated by relating the magnitude of the motion caused by atrial contraction to the total diastolic AV plane motion at the respective sites. These left atrial contributions were regarded as the regional diastolic function of the respective LV sites. The global LV diastolic function was determined from the left atrial contribution to total AV plane motion from the above four sites. Patients with anterior MI had a significantly lower ejection fraction than those with inferior MI (41% and 49%, respectively; P < 0.01). Compared with age‐matched healthy subjects, the regional atrial contribution to diastolic filling was significantly higher at the anterior wall in anterior MI (38% and 52%, respectively; P < 0.001) and at the inferior wall in inferior MI (43% and 53%, respectively; P < 0.01). The atrial contribution to global LV filling was increased in anterior MI (48% compared with 42% in healthy subjects; P < 0.05) but not in inferior MI. These findings suggest that the diastolic AV plane displacement (AVPD) may be used to assess both the regional and the global diastolic function in patients following an MI.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background The inclusion of large, heterogeneous groups of patients for coronary bypass grafting (CABG) surgery has resulted in a more mixed treatment outcome. Thus it becomes important to identify ...patients who are less likely to benefit from surgery or who may require additional support to improve treatment outcome. The aim of the present study was to examine whether psychological status measured before CABG can contribute to prediction of short- and long-term outcomes of the surgery.
Methods and Results One hundred seventy-one consecutive patients from two large university hospitals in Stockholm completed a psychosocial questionnaire before being scheduled for surgery. One year after CABG, patients again completed the questionnaire. Follow-up of medical charts was conducted during the first 3 years after surgery. All major cardiac events (cardiac death, definite myocardial infarction, revascularization, and unstable angina verified by angiography or myocardial scintigraphy) were recorded. Although the overall effect of surgery was excellent in the majority of cases, the patients exhibiting a high degree of distress (anxiety, depression, and tiredness) before surgery assessed their status as being much worse both before the operation and at the 1-year follow-up. Equally important was the fact that patients considered distressed before surgery had significantly higher rates of cardiac events (16%) in the 3-year follow-up period compared with nondistressed patients (5%) (chi-square = 5.11, degrees of freedom = 1,
p < 0.02).
Conclusions Systematic evaluation and treatment of emotional distress in the candidates for coronary revascularization may be expected to result in more optimal subjective results and a reduction in the number of serious cardiac events after surgery. (Am Heart J 1998;136:510-7.)
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background: Most studies concerning exercise electrocardiography (ECG) testing after acute myocardial infarction (AMI) were carried out in the prethrombolytic era. ST‐segment elevation in the ...infarction area during exercise has usually been interpreted as indicating the presence of dyskinesia as a result of extensive left ventricle damage.
Hypothesis: This study was undertaken to evaluate the contributions of exercise‐induced ST‐segment elevation and T‐wave pseudonormalization to the assessment of myocardial viability in patients with thrombolyzed myocardial infarction (MI), compared with low‐dose dobutamine echocardiography.
Methods: The study comprised 52 consecutive patients with AMI treated with thrombolysis. All patients underwent low‐dose dobutamine echocardiography and symptom‐limited exercise testing before discharge.
Nineteen patients showed ST‐segment elevation (Group 1), 9 showed isolated T‐wave pseudonormalization (Group 2), and 24 patients did not exhibit either of these ST‐T segment changes (Group 3). Low‐dose dobutamine echocardiography revealed evidence of viability in 16 patients (84%) in Group 1 (p=0.01), 5 (56%) in Group 2 (p=NS), and 11 patients (46%) in Group 3 (p = NS).
Conclusion: Exercise‐induced ST‐segment elevation may contribute to the evaluation of myocardial viability in patients with AMI treated with thrombolysis. However, in the absence of exercise‐induced ST‐segment elevation, further noninvasive studies might be indicated to assess myocardial viability.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The aim of the study was to characterize left ventricular (LV) function by Doppler tissue imaging (DTI) after a first myocardial infarction (MI) where the conventional echo-Doppler parameters showed ...no abnormalities.
Out of 202 patients who were referred for an echocardiogram, 19 patients were previously healthy and had a normal ejection fraction and no wall motion abnormalities at echocardiogram. These 19 patients were compared with 16 age-matched healthy subjects (HS). The longitudinal LV function was assessed using the mitral annular velocities (mean value from four different sites of the LV) determined by DTI.
The patients with MI had significantly reduced peak systolic and peak early diastolic mitral annular velocities compared to HS (8.6 v. 9.7 cm/s, P<0.001 for systolic velocity, and 10.9 v. 12.3 cm/s, P<0.01 for diastolic velocity, respectively). The patients had normal diastolic LV function assessed by the conventional Doppler echocardiogram (e.g. transmitral flow, IVRT and pulmonary venous flow patterns). To assess the LV filling pressure, the ratio of the transmitral early wave velocity assessed by conventional echo-Doppler and peak early diastolic mitral annular velocity determined by DTI (E/Edti) was used. The E/Edti was significantly higher in patients than in HS (7.0 v. 5.7, P<0.05).
Previously healthy subjects who are suffering from a first MI and showing normal systolic and diastolic LV function, determined by conventional echo-Doppler methods, show decreased mitral annular systolic and diastolic velocities determined by DTI compared to healthy subjects. This is probably evidence of mild subendocardial damage due to MI that remains undetected by conventional echo-Doppler methods.
Assessments of compromised myocardium and infarct size early after thrombolytic treatment in acute myocardial infarction (AMI) are important for risk stratification and for treatment management. We ...have therefore evaluated the clinical usefulness of myocardial perfusion scintigraphy (MIBI-SPECT) for the assessment of myocardial viability early after AMI.
Seventy-one patients 53 men and 18 women, aged 64 +/- 9 years (range 45-75 years) with AMI treated by thrombolysis took part in this prospective study at University Hospital, Stockholm, Sweden. Sixty of them underwent adenosine-stress and resting MIBI-SPECT 2-4 days after AMI, and 11 were examined only at rest. Six months after the AMI, a repeat MIBI-SPECT at rest was obtained for comparison.
All patients had significant perfusion defects compared with an age- and sex-matched healthy reference population. Seventy-six percent of the patients able to undergo a complete adenosine-stress and rest SPECT showed signs of reversible perfusion defects. Defect size (extent) and severity at rest decreased between the tests at 2-5 days and 6 months after AMI (P < 0.001). Reversible perfusion defects early after AMI were not related to spontaneous improvement of myocardial perfusion 6 months later. Early, semiquantitative MIBI-SPECT was not able to predict final infarct size as measured by resting perfusion data 6 months after AMI, regardless of whether the threshold value was set at 30, 40, 50 or 60% of the maximal isotope uptake in the early resting scan.
Myocardial perfusion scintigraphy with adenosine-stress and resting MIBI-SPECT early after AMI underestimates myocardial viability in the majority of patients treated with thrombolytic agents. Neither reversible perfusion defects nor regional semi-quantitative perfusion data appear to predict spontaneous improvement of perfusion 6 months after AMI.
In patients with thrombolyzed acute myocardial infarction, early assessment of the final infarct size is difficult because spontaneous recovery of perfusion and function of the left ventricle may be ...delayed. This study was undertaken to evaluate the ability of predischarge low-dose dobutamine echocardiography to predict late spontaneous recovery of perfusion assessed by single-photon emission computed tomography after acute myocardial infarction. We prospectively studied 53 consecutive patients with myocardial infarction treated with thrombolysis. Low-dose dobutamine echocardiography and resting (99m)Tc-sestamibi single-photon emission computed tomography (MIBI SPECT) were performed 4 +/- 2 days after infarction. A follow-up SPECT study was carried out in 45 patients after 6 months. Myocardial recovery was defined as a reduction of SPECT defect size by more than 10% at follow-up compared with the early study. In 25 of the 45 patients, the size of the left ventricular perfusion defect decreased significantly from 42% +/- 16% to 27% +/- 10% (group 1), whereas in the remaining 20 patients it showed no significant change (group 2). Predischarge low-dose dobutamine echocardiography showed a significant improvement in wall motion score index compared with baseline in group 1, from 1.62 +/- 0.28 to 1.41 +/- 0.24, P <.001, whereas in group 2 this index remained without significant change. Predischarge low-dose dobutamine echocardiography is an accurate tool for prediction of late recovery of myocardial perfusion after acute myocardial infarction treated with thrombolysis.
Abstract only Background: Increased hyperemic microcirculatory resistance and/or low coronary flow reserve (CFR) diagnostic criteria for coronary microvascular disease in ischemia with no obstructive ...coronary arteries (INOCA). For optimal therapy pathophysiological mechanisms need to be determined. Aim: To investigate plasma levels of markers of i) endothelial dysfunction (syndecan-1, E-selectin, thrombomodulin and hyaluronan) and ii) myocardial fibrosis (procollagen type I carboxy-terminal propeptide PICP, suppression of tumorigenicity 2 ST2, and tissue inhibitor of metalloproteinases-1TIMP-1) in relation to the index of microcirculatory resistance (IMR) and CFR in INOCA. Methods: Measurements of corrected IMR and CFR were determined in the LAD using thermodilution technique during coronary angiography (CA) in chronic coronary syndrome (CCS) patients. Plasma biomarkers were quantified using an ELISA and the association between each biomarker and i) IMR and ii) CFR was analyzed using linear regression. Results: We selected 162 random patients with INOCA from a cohort of 503 all-comer CCS patients with no congestive heart failure that underwent CA with measurements of CFR and IMR in the LAD. The mean age was 65 ±10 years and 101 (62.3%) were male. Median IMR and CFR were 19.1 (interquartile range IQR 11.9-30.7) and 3.5 (IQR 2.3-5.1) respectively. IMR was associated with syndecan-1 (Figure 1A) but not with PICP (Figure 1C) or the other biomarkers. CFR was inversely associated with syndecan-1 (Figure 1B), PICP (Figure 1D), and E-selectin (p=0.049). Conclusion: IMR is associated with increasing plasma levels of syndecan-1 but not with myocardial fibrosis, indicating endothelial dysfunction, with glycocalyx shedding, to be involved in high hyperemic microcirculatory resistance in INOCA. Low CFR is also associated with PICP indicating involvement of myocardial fibrosis in coronary microvascular disease in INOCA.
Schizosaccharomyces pombe is an outstanding model organism for cell biological investigations, yet the range of useful and well-characterized fluorescent proteins (XFPs) is limited. We generated and ...characterized three recoded fluorescent proteins for 3-color analysis in S.pombe, Super-folder GFP, monomeric Kusabira Orange 2 and E2Crimson. Upon optimization and expression in S. pombe, the three proteins enabled sensitive simultaneous 3-color detection capability. Furthermore, we describe a strategy that combines a pulse-chase approach and mathematical modeling to quantify the maturation kinetics of these proteins in vivo. We observed maturation kinetics in S. pombe that are expected from those described for these proteins in vitro and/or in other cell types, but also unpredicted behaviors. Our studies provide a kinetically-characterized, integrated three-color XFP toolbox for S. pombe.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract only
Background:
The prognostic implications of coronary microvascular dysfunction in an all-comer cohort with chronic coronary syndrome (CCS) are not known.
Aim:
To investigate the ...association of baseline resistance index (BRI), index of microcirculatory resistance (IMR), and thermodilution-derived resting- and hyperemic flow velocities (RFV and HFV) with the primary composite endpoint consisting of all-cause mortality, incident myocardial infarction (MI) or hospitalization due to congestive heart failure (CHF) in CCS.
Methods:
CCS patients undergoing elective coronary angiography (CA) were included. Measurements of corrected IMR, BRI and mean transit time at baseline (Tmn
base
) and during hyperemia (Tmn
hyp
) were obtained in the LAD. RFV and HFV were calculated as 1/Tmn
base
and 1/Tmn
hyp
, respectively. Cox-regression was performed and Kaplan-Meier plots were constructed.
Results:
We included 503 patients before the coronary anatomy was known and thermodilution measurements in the LAD were obtained in 413 patients. Median age was 68 (IQR 61-74), 127 (25%) were women and 151 (37%) had a flow-limiting epicardial lesion in the LAD. Median follow-up was 5.3 years (IQR 3.0-6.6) and there were 57 events. Log
10
BRI was inversely associated with the primary endpoint before and after fractional flow reserve (FFR) adjustments (HR 0.64 95% CI 0.42 - 0.97; Figure 1A). Log
10
IMR was not associated with the primary endpoint (HR 0.94 95% CI 0.61 - 1.5; Figure 1B). Log
10
RFV was associated with the primary endpoint before and after FFR- adjustment (HR 1.8 95% CI 1.2 - 2.7) whereas log
10
HFV was not (HR 1.2 95% CI 0.75-1.8).
Conclusion:
Low microcirculatory resting resistance and high coronary resting flow velocity in the LAD, indicating impaired autoregulation, were associated with all-cause death, MI and/or CHF in CCS whereas hyperemic microcirculatory resistance and flow were not. Resting flow indices can be used for risk evaluation in patients with CCS undergoing CA.
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