Tsutomu Toshida

Impact of depression on masked hypertension and variability in home blood pressure in treated hypertensive patients.

This study was conducted to determine the effects of depression and/or insomnia on masked hypertension (MHT) compared with other types of HT and on variability in home-measured blood pressure (HBP) and clinic BP (CBP). Three hundred and twenty-eight hypertensives (132 women) aged 68±10 years were classified into four BP types: controlled HT (CHT), white-coat HT, MHT and sustained HT (SHT), based on CBP (140/90 mm Hg) and morning HBP (135/85 mm Hg) measurements. A score of ⩾16 on the Center for Epidemiologic Studies Depression Scale (CES-D) was defined as depression. The mean values and s.d. of BP were calculated from measurements taken during the 14 consecutive days just before the CES-D evaluation. Compared with the CHT group, the risk of depression was 2.77-fold higher in the SHT group and even higher in the MHT group (7.02-fold). The association between depression and MHT was augmented in the presence of insomnia and was somewhat stronger in women. A HBP variability index defined as s.d./mean BPs in both morning and night time was significantly higher in MHT than in the other BP types, whereas that of CBP was not. Both morning and night-time HBP variability were significantly higher in depressive patients than in non-depressives. These suggest that depression is associated with MHT and that increases both morning and night-time HBP variability but not CBP variability. Physicians should be mindful of mental stresses such as depression in their hypertensive patients when forming strategies to control BP over the diurnal cycle.

Effect of Systemic Blood Pressure on Microcollateral Circulation Evaluated by Real-Time Contrast Echocardiography

BACKGROUND In acute myocardial infarction, residual collateral-derived myocardial blood flow (CBF) within the ischemic area is one of the major determinants of infarct size. Management of systemic blood pressure (sBP) related to maintain collateral circulation is still difficult. The aim of this study was to reveal the influence of sBP on the rescue of area at risk by collateral circulation. METHODS Real-time myocardial contrast echocardiography just after the onset of complete occlusion of the left circumflex coronary artery was performed in collateral-rich open-chest dogs. The video intensity of the ischemic area was evaluated during the occlusion and the CBF (A x beta) was calculated from a replenishment curve: y = A (1 - e(-beta t)). To analyze the effect of sBP on the collateral circulation, sBP was altered by infusion of nitroglycerin or etilefrine hydrochloride. To evaluate the defect size (%DS), every end-systolic myocardial contrast echocardiography image after left circumflex coronary artery occlusion was converted into binary images using custom offline software. RESULTS The %DS increased and CBF slightly decreased at low sBP. The %DS decreased and CBF increased at high sBP. At excessively high sBP, %DS increased and CBF decreased again. CONCLUSION Real-time myocardial contrast echocardiography, which is a useful noninvasive method to evaluate the collateral perfusion quantitatively, has a crucial role in the decision of patient treatment and management strategy of acute myocardial infarction.

Myocardial blood flow parameters derived from contrast replenishment using harmonic power doppler imaging are underestimated by ultrasound signal attenuation

The effect of ultrasound signal attenuation on myocardial blood flow parameters derived from contrast replenishment was evaluated using harmonic gray-scale (HGS) and harmonic power Doppler (HPD) imaging. In vitro experiments were performed in a flow model, whereas in vivo experiments were performed in 5 open-chest dogs. In each study, intermittent HGS and HPD images were acquired at various pulsing intervals during contrast infusion. A silicone pad was interposed between the transducer and target region to simulate attenuation conditions. Baseline-subtracted HGS and HPD signal intensities were measured with and without silicone pad, and myocardial blood flow parameters A and beta were calculated using contrast replenishment. Attenuation with HGS images could be offset by baseline subtraction, as baseline images provided the reference for attenuation. However, attenuation with HPD images could not be compensated for, as baseline signal intensity was theoretically 0. In HGS mode, silicone attenuation produced no significant decreases in A and beta. In HPD mode, however, A and beta were significantly decreased by silicone attenuation (A, P <.001; beta, P <.05). Compared with nonattenuated regions, myocardial blood flow parameters in attenuated regions are underestimated when HPD imaging is used. Baseline-subtracted HGS imaging may be useful to compensate for thoracic wall attenuation.

Reversible T‐Wave Inversions and Neurogenic Myocardial Stunning in a Patient with Recurrent Stress‐Induced Cardiomyopathy

A 72‐year‐old female was diagnosed as a stress‐induced cardiomyopathy from apical ballooning pattern of left ventricular dysfunction without coronary artery stenosis after the mental stress. ECG showed the transient T‐wave inversions after the ST‐segment elevations. By the mental stress after 1 year, she showed a transient dysfunction with similar ECG changes again. T‐wave inversions recovered earlier, and cardiac sympathetic dysfunction showed a lighter response corresponding to the less severe dysfunction than those after the first onset. Wellens’ ECG pattern was associated with the degree of neurogenic myocardial stunning with sympathetic hyperinnervation caused by mental stress.

Nicorandil preserves collateral circulation even at low systemic pressure in comparison with nitroglycerin: real-time myocardial contrast echocardiographic study

lar damage in patrents with AMI. We investigated MCE with harmonic power Doppler (HPD), CFR and CF by using transthoracic echocardiography (TTE) in predicting func- tional recovery. Methods: We performed MCE (SONOSSSOO, Philips) by using 1:4 inter- mittent HPD with Levovist at rest and during ATP in 30 patients two weeks after anterior AMI. Peak videointenstty was measured within the risk and control regions. The peak intensity ratios of the risk area to the control area (PIR) at rest and during hyperemia were calculated. We measured CFR of the left anterior descending artery (LAD) two weeks after AMI. CF of LAD by TTE was also obtained within 24 hours after successfully recanalization

Three-dimensional reconstruction of coronary arteriole plexus image by contrast echocardiography using high frequency transducer

OBJECTIVE This study was established to examine the efficacy of a high-frequency liner probe for visualizing fine anatomy of coronary microcirculation. METHODS The vessel size and its velocity-time integral at the anterior wall in dogs by real-time contrast echocardiography with high-frequency liner probe and pulse Doppler methods, and the coronary flow volume, were measured before and after adenosine triphosphate injection. A 3-dimensional (3D) image was reconstructed by the built-in 3D system using intermittent flash echocardiographic images. RESULTS The increments of flow volume calculated from vessel sizes and velocity-time integral were well correlated with those of coronary flow volume. Using intermittent flash echocardiographic images, fine dots and lines of contrast echocardiographic-expected arterioles were evident, and easily and quickly reconstructed as coronary plexus by 3D system. CONCLUSION A high-frequency liner probe provides the fine-vessel images to evaluate those morphologic changes; a 3D reconstruction image could provide new information about coronary arterioles.

Real-time myocardial contrast echocardiography reveals microvessel recruitment soon after coronary occlusion

Background and Aim: Collateral flow at the micro-vessel level is important to salvage the myocardium after acute coronary obstruction, although larger collateral vessels are observed by coronary angiography. The aim of this study was to elucidate the presence of micro-collateral channel by real-time myocardial contrast echocardiography (MCE). Methods: Short axis view of the left ventricle was recorded using real -time imaging by Sequoia 512 during infusion of 0.1 ml/min of Optison( in 17 open-chest dogs. All bubbles were destroyed by one-second exposur e of high acoustic power just after LCx occlusion. The territory of LCx was divided into 3 areas (1 Core and 2 Border zones), and the systolic wall thickening (s-WT) and contrast echo video intensity (VI) were evaluated in each zone just before and 20 seconds after LCx occlusion. It was defined that the collateral channels were good when the mean VI of core and border zones were over 20/256 gray level despite complete occlusion of LCx. The flow volume of left anterior descending coronary artery (LAD) was measured by an ultrasonic flowmeter. Results: It was determined that 7 cases had good collateral channels and other 10 cases had not. The area of risk was gradually but definitely opacified in Good group. Total VI of 3zones was significantly higher in Good group than those in Poor group (69.8+40.3 vs 12.3+6.4, p<0.001). Even in Good group, the VI of core zone was significantly lower than that of border zone (11.3+11.2 vs. 35.3+17.4, p<0.001). Mean s-WT of 3 zones was significantly higher in Good group than those in Poor group (18.8+8.6 vs. 5.5+3.3, p<0.001). S-WT correlated well with VI in all zones of all cases (r=0.916, p<0.001). The LAD flow volume increased 26.2+13.6% during LCx occlusion in Good group, while 10.5+5.3 % in Poor group. Conclusion: It is revealed that real-time MCE demonstrates the recruitment of a fine and thin collateral channel appearing soon after coronary occlusion. This finding has not been elucidated so far by other modalities. Real-time MCE can elucidate the mechanism of myocardial salvage after acute coronary obstruction in both clinical and experimental aspect.