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Objective: To test the hypothesis that impaired coronary and myocardial blood flow are linked with increased myocyte apoptosis, thus establishing a link between pressure overload and left ventricular (LV) remodelling. Methods and results: Peak diastolic coronary blood flow velocity (CBFV) was evaluated at transthoracic Doppler echocardiography, and signal intensity (SI) and the rate of SI rise (β) were measured at myocardial contrast echocardiography in 11 patients with severe aortic stenosis and LV hypertrophy. In the same patients, biopsies were obtained from the anterolateral LV free wall during surgery and analysed for cardiomyocyte apoptosis. LV mass corrected CBFV (CBFVI) was significantly lower in patients than in controls (median 0.100 cm g/s (interquartile range 0.07–0.115) v 0.130 cm g/s (0.130–0.160), p = 0.002). Similarly, SI*β was significantly lower in patients than in controls (11 1/s (8–66) v 83 1/s (73–95), p = 0.001). Apoptotic rate was increased in aortic stenosis more than 100-fold versus controls (1.2% (0.8–1.4) v 0.01% (0.01–0.01), p < 0.001) and inversely correlated with lower CBFVI and SI*β (r = -0.77, p = 0.001 for both). Conclusions: Patients with severe aortic stenosis and LV hypertrophy have impaired myocardial perfusion, which is associated with enhanced cardiomyocyte apoptosis. Impaired myocardial perfusion and the ensuing oxygen demand-supply imbalance may, at least partially, be responsible for increased apoptosis and possible transition to heart failure, thus establishing a link between pressure overload, LV remodelling, and heart failure. [ABSTRACT FROM AUTHOR]

Objective: To identify in humans the temporal patterns of no reflow and their functional implications.Methods: 24 patients with first acute myocardial infarction and successful coronary recanalisation by recombinant tissue-type plasminogen activator (n = 15) or primary percutaneous transluminal coronary angioplasty (n = 9) were studied by myocardial contrast echocardiography within 24 hours of recanalisation and at one month's follow up. Myocardial contrast echocardiography was performed by intermittent harmonic power Doppler and intravenous Levovist. The regional contrast score index (CSI) was calculated within dysfunctioning myocardium. Videointensity was measured (dB) within risk and control areas and their ratio was calculated.Results: In 8 patients reflow was observed at 24 hours and persisted at one month. Conversely in 16 patients areas of no reflow were detectable at 24 hours. At one month, no reflow was spontaneously reversible in 9 patients (mean (SD) CSI and videointensity ratio improved from 2.5 (0.5) to 1.4 (0.6) and from 0.6 (0.1) to 0.7 (0.1), respectively; p < 0.05) and was sustained in the remaining 7 patients (CSI and videointensity ratio remained unchanged from 2.6 (0.6) to 2.6 (0.5) and from 0.5 (0.2) to 0.5 (0.2), respectively; NS). Left ventricular function improved significantly in patients with reflow and reversible no reflow. Volumes were enlarged only in patients with sustained no reflow.Conclusions: No reflow detected at 24 hours may be sustained or spontaneously reversible at one month. Such reversibility of the phenomenon is associated with preserved left ventricular volumes and function. Clarification of the mechanisms of delayed reversibility may lead to tailored treatment of no reflow even in the subacute phase of myocardial infarction. [ABSTRACT FROM AUTHOR]

The myocardial performance index represents an easy and reproducible parameter of both systolic and diastolic left ventricular function for the risk stratification of patients following acute myocardial infarction [ABSTRACT FROM AUTHOR]

The article presents a study, which focuses on quantifying myocardial perfusion using echocardiography. For myocardial contrast echocardiography, the process of development has been particularly long since the display techniques have been hampered by several pitfalls, thus generating unreliable quantitative information. The authors begin calibrating in vitro the contrast signal intensity generated by micro bubbles of Levovist within the insonified ultrasound field, thus confirming an excellent linear correlation between bubble concentration and contrast signal intensity obtained by harmonic power Doppler. Then the authors developed a method to quantitate the contrast intensity in vivo, compensating for the spatial heterogeneity of the signal among different myocardial walls generated by the acoustic field in homogeneity as well as by distal wall contrast attenuation. Finally, they verified the clinical meaning of the generated numbers comparing normal segments with segments with perfusion defects at single photon emission computed tomography.

The article presents a study about the safety of early Granulocyte-colony stimulating factor (G-CSF) administration after acute myocardial infarction (AMI). It has been mentioned this study aims to assess the safety and the potential efficacy on cardiac function and perfusion of G-CSF administration. In this study, there were eight patients enrolled with a first anterior AMI with various qualifications.

The article presents case of a 75 year old man who was admitted to coronary care unit with anterolateral ST elevation myocardial infarction. After intravenous treatment with aspirin and nitrates, the patient underwent urgent coronary angiography that documented occlusion of the proximal left anterior descending coronary artery (LAD) with TIMI 0 flow. During the procedure "dual LAD" anatomy was documented with a bifurcation of the LAD into a large septal branch and a large diagonal branch. Twelve hours after percutaneous coronary intervention, a myocardial contrast echo study was performed using a Sequoia ultrasound machine and intravenous SonoVue. The patient had a large area of microvascular obstruction at the level of the apex, septum, and posterolateral wall.

We designed the present study (1) to investigate the velocities of longitudinal movement of the human left ventricle by pulsed-wave tissue Doppler (PWTD) imaging; (2) to test the hypothesis that a heterogeneous pattern of longitudinal systolic and diastolic velocities exists among individual left ventricular wall segments; (3) to establish the range of this heterogeneity, and (4) to correlate the function of individual segments with the known orientation of myocardial fibers. PWTD is a novel ultrasound method to quantify myocardial contraction and relaxation velocities. In 27 young normal subjects, PWTD peak values of longitudinal systolic and diastolic velocities were measured for 12 left ventricular segments visualized from the apical window. The PWTD sampling of each myocardial segment resulted in a triphasic velocity curve during each cardiac cycle: a systolic velocity wave (S) directed toward the transducer, and an early diastolic (E) and a late diastolic (A) velocity wave away from the transducer. A heterogeneous pattern of systolic and diastolic myocardial velocities was observed between individual wall segments as well as for the basal and midsegments of each myocardial wall. The difference between the highest and lowest values for S was 38.4% in the basal segments and 56.3% in the midwall segments. The difference between low and high velocities for E was 61.4% in the basal and 38.2% in the midsegments; for A the difference was 29.5% in the basal and 32.6% in the midsegments. In general, lower velocity values were found in the septum with higher basal to midwall difference. The lateral and posterior walls had higher, but more uniform, velocities. PWTD enables the quantitative assessment of regional systolic and diastolic myocardial velocities. Substantial heterogeneity of velocities exists within individual myocardial segments, and must be taken into account in any clinical application. The observed heterogeneity in longitudinal function is consistent with the known spatial distribution of myocardial fibers. [ABSTRACT FROM AUTHOR]