Systolic Ratio Research Articles

Sharp systolic inequalities for Reeb flows on the three-sphere

The systolic ratio of a contact form $\alpha$ on the three-sphere is the quantity \[ \rho_{\mathrm{sys}}(\alpha) = \frac{T_{\min}(\alpha)^2}{\mathrm{vol}(S^3,\alpha\wedge d\alpha)}, \] where $T_{\min}(\alpha)$ is the minimal period of closed Reeb orbits on $(S^3,\alpha)$. A Zoll contact form is a contact form such that all the orbits of the corresponding Reeb flow are closed and have the same period. Our first main result is that $\rho_{\mathrm{sys}}\leq 1$ in a neighbourhood of the space of Zoll contact forms on $S^3$, with equality holding precisely at Zoll contact forms. This implies a particular case of a conjecture of Viterbo, a local middle-dimensional non-squeezing theorem, and a sharp systolic inequality for Finsler metrics on the two-sphere which are close to Zoll ones. Our second main result is that $\rho_{\mathrm{sys}}$ is unbounded from above on the space of tight contact forms on $S^3$.

The Impact of Sevoflurane on Coupling of the Left Ventricular-to-Systemic Vasculature in Rats With Chronic Pulmonary Hypertension

The relationship between left ventricular function and afterload has not been investigated as much as the right ventricular function under chronic pulmonary hypertension (PH) during anesthesia. This study was designed to investigate effects of sevoflurane on the intrinsic coupling relationship between the left ventricle and systemic vasculature in the presence of PH. A randomized, controlled study. University hospital. Sprague-Dawley rats. Monocrotaline (MCT) was injected intraperitoneally to induce a PH model. Four weeks later, rats with MCT injection demonstrated significantly increased pulmonary arterial pressure and right/left ventricular systolic ratio of ventricular pressure (p < 0.001). Rats were treated with 1.5% sevoflurane inhalation. The PV catheters were inserted and left ventricular pressure-volume loops were measured at baseline, 30, 60, and 90 minutes during sevoflurane treatment. Preload recruitable stroke work and end-systolic elastance were decreased markedly in rats with MCT injection (p < 0.05). However, arterial elastance decreased similarly in both groups. Sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) level was decreased and the expression of phospholamban (PLB) was increased in the PH group and after sevoflurane treatment. PH rats suffered further SERCA2/PLB ratio decrease from their already low baseline. The left ventricular contractility and ventricular-vascular coupling were decreased in rats with PH after sevoflurane inhalation. Sevoflurane reduced SERCA2a expression and increased PLB expression in PH rats. This partially could explain why the LV contractility and ventricular-to-vasculature coupling of PH rats were attenuated after sevoflurane treatment.

Abstract 11329: Risk Factors of Thromboembolism in Patients With Left Ventricular Noncompaction

Introduction: Left ventricular noncompaction (LVNC) is a newly recognized cardiomyopathy characterized by a pattern of prominent trabeculation and deep recesses. LVNC can lead to progressive left ventricular (LV) dysfunction and thromboembolism. However, there are few reports that the factors develop thromboembolism in patients with LVNC. Purpose: This study was sought to investigate a difference of characteristics in patients with LVNC developing thromboembolism. Methods: We retrospectively studied 43 patients (age 61 ± 17 years, 32 male) fulfilling the diagnostic criteria of LVNC out of 7842 adults patients (ejection fraction (EF)≦60%) undergoing echocardiography in our hospital between 2012 and 2015. A thickness of the noncompacted endocardial and the compacted epicardial layers was measured at the site of maximal thickness to calculate the ratio of noncompacted to compacted layer (NC/C). The LV wall was divided into five segments (apical, inferior, lateral, anterior and septal) to describe the location of the noncompacted segments. We defined the diagnostic criteria of LVNC as a presence of prominent trabeculation and deep recesses of LV on more than one segment and a maximal end systolic ratio of NC/C≧2.0. Results: LVEF was 38.0 ± 13.0%, LV end-diastolic diameter was 60.0 ± 9.5mm and left atrial diameter (LAD) was 43.8 ± 8.8 mm, respectively. Eight patients (18.6%) were complicated with thromboembolism. There were no significant difference between the patients with thromboembolism and without them on atrial fibrillation, EF and the dilation LAD. The multivariate analysis showed that the patients with thromboembolism had a significantly larger prevalence of patients with a pattern of prominent trabeculation and deep recesses of LV on more than two segments (Odds ratio 6.964, P=0.050) and the height of noncompacted layer ≧ 15 mm (Odds ratio 4.879, P=0.049). Conclusions: The findings such as more than two segments with a pattern of prominent trabeculation and deep recesses of LV and the height of noncompacted layer ≧ 15mm on echocardiography were associated with thromboembolism in patients with LVNC. Anticoagulants should be considered to prevent the patients from thromboembolism regardless of LV function and arrhythmia.

Biomimetic Cardiac Tissue Model Enables the Adaption of Human Induced Pluripotent Stem Cell Cardiomyocytes to Physiological Hemodynamic Loads.

Induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) provide a human source of cardiomyocytes for use in cardiovascular research and regenerative medicine. However, attempts to use these cells in vivo have resulted in drastic cell death caused by mechanical, metabolic, and/or exogenous factors. To explore this issue, we designed a Biomimetic Cardiac Tissue Model (BCTM) where various parameters associated with heart function including heart rate, peak-systolic pressure, end-diastolic pressure and volume, end-systolic pressure and volume, and ratio of systole to diastole can all be precisely manipulated to apply hemodynamic loading to culture cells. Using the BCTM, two causes of low survivability in current cardiac stem cell therapies, mechanical and metabolic, were explored. iPSC-CMs were subject to physiologically relevant mechanical loading (50 mmHg systolic, 10% biaxial stretch) in either a low- or high-serum environment and mechanical loads were applied either immediately or gradually. Results confirm that iPSC-CMs subject to mechanical loading in low-serum conditions experienced widespread cell death. The rate of application of stress also played an important role in adaptability to mechanical loading. Under high-serum conditions, iPSC-CMs subject to gradual imposition of stress were comparable to iPSC-CMs maintained in static culture when evaluated in terms of cell viability, sarcomeric structure, action potentials and conduction velocities. In contrast, iPSC-CMs that were immediately exposed to mechanical loading had significantly lower cell viability, destruction of sarcomeres, smaller action potentials, and lower conduction velocities. We report that iPSC-CMs survival under physiologically relevant hemodynamic stress requires gradual imposition of mechanical loads in a nutrient-rich environment.

Pregnancy in a patient with acute Porphyria

A 27 years old female was diagnosed to have acute intermittent porphyria in 1997. In 2002 she became pregnant. The first trimester was uneventful obstetrically but the duration, frequency and severity of porphyria attacks increased. As the pregnancy advanced to second trimester the condition of patient deteriorated. The symptoms were continuous with no period of relief. In the third trimester she became increasingly irritable and dyspnoeic, and developed facial edema, muscle weakness, and fecal and urinary incontinence. At 33 weeks of gestation USG showed absent liquor and decreased fetal movements; S/D (systolic diastolic ratio) was increased (&gt;4.3). Elective Cesarean-section was performed at 33 weeks. Her condition settled in one week. Porphyria is an uncommon disorder. It affects women more frequently than men. Not only it has adverse effects on pregnancy but the frequency of porphyria attacks also increases during pregnancy. We herewith present a case report of a female with acute intermittent porphyria who conceived.

Immediate post renal transplant period and hypertension: concordance between clinic and ambulatory blood pressure

Background: Markedly increased pulse wave velocity (PWV) with aging has been reported in numerous studies. Arterial wave reflection (WR) timing based on of the Augmentation Index (AI) framework does not change appreciably, despite increased PWV. The cause for this apparent discordance has not been established. Although a distal shift of reflecting sites has been proposed, this proposition has been exclusively based on the timing of the inflection point, which is a very limited approach. We hypothesize that AI is not capable of detecting early-systolic effects of reflection, particularly when PWV is high, leading to an apparent reflection-free period in early ejection. Methods: Simultaneous aortic pressure and flow were measured in anesthetized, open-chest dogs (n1⁄45). Intravenous infusion of methoxamine (MTX) and nitroprusside (NTP) were used to increase and decrease WRs, respectively. A coupled left ventricle-arterial system model was used to alter reflection magnitude and timing. Effects of reflection in early-systole were assessed with a systolic pressure-flow ratio (SPFR). Results: SPFR in the case of NTP remained close to aortic characteristic impedance (Zc) [horizontal dashed line] up until peak flow (Fig.1A). In control and MTX, SPFR grew increasingly divergent from Zc before peak flow (Fig.1B-C). Even when an inflection point is observed on the pressure waveform (Fig.1D, inset), SPFR diverges from Zc before the inflection, indicative of early-systole WRs. Modeling studies confirmed the dog experiments in a noise-free environment; only when wave reflections are substantially delayed and/or minimal does SPFR equal Zc in earlysystole. Divergence from this relation is due to WRs. Conclusion:WRs can alter pressure-flow relations in early-systole, prior to time of peak flow and the inflection point on the pressure waveform. Since AI is blind to early-systolic WRs, it should not be used to assess WR timing, especially when PWV is high. This is a particularly important limitation of AI to recognize when studying older subjects as well as those with hypertension in which PWV is elevated. When an appropriate method is used to gauge WR magnitude and timing in earlysystole, elevated PWV is indeed associated with earlier effects of reflections.

Abstract 70: Novel Multi-target Compound, Agonist of Adenosine Receptor and Inhibitor of Phosphodiesterase 5, Ameliorates Monocrotaline-induced Pulmonary Hypertension in Rats

Aims: Pulmonary hypertension (PH) is a disease that results in right ventricular (RV) dysfunction and premature death. This work investigated the effects of LASSBio-1386, a compound with dual target, activation of the adenosine A 2A receptor and inhibition of phosphodiesterase 5 in rats with monocrotaline (MCT)-induced PH. Methods and Results: Protocols were approved by Animal Care and Use Committee at Universidade Federal do Rio de Janeiro. Male Wistar rats received a single intraperitoneal injection of MCT (60 mg/kg) for PH induction. Experimental groups were: control, MCT + vehicle (DMSO), MCT + LASSBio-1386 (100 μmol/kg/day p.o.) and MCT + Sildenafil (100 μmol/kg/day p.o.). Animals were treated with vehicle or drug for 14 days after the onset of disease (n = 6 per group). Treadmill test and transthoracic echocardiography were performed to access exercise capacity and cardiac function, respectively. Right ventricular systolic pressure (RVSP) and ratio between RV and body weight (RV/BW) were analyzed. Exercise capacity (m.kg) was reduced from 1336.2 ± 82.2(control) to 479.7 ± 75.5 (MCT+ vehicle) and recovered to 1357.0 ± 87.8 and 1221.0 ± 96.8 after treatment with LASSBio-1386 and sildenafil, respectively. Pulmonary acceleration time (PAT) (ms) was reduced from 45.3 ± 0.8 (control) to 21.9 ± 0.3 in MCT + vehicle group ( P &lt; 0.05) and restored to 42.9 ± 0.7 in MCT + LASSBio-1386 group, but it was only partially restored to 37.8 ± 1.3 (ms) in MCT + Sildenafil-treated group. RVSP (mmHg) was increased from 27.1 ± 0.7 (control) to 52.9 ± 1.5 in the PH rats and was reduced to 29.1 ± 1.0 and to 31.8 ± 0.6 after treatment with LASSBio-1386 and sildenafil. PH induced an increase of RV/BW (mg/g) from 0.62 ± 0.03 (control) to 1.81 ± 0.20 which was reduced to 0.70 ± 0.07 after administration of LASSBio-1386. Sildenafil treatment did not reverse the RV hypertrophy in PH rats (RV/BW = 1.52 ± 0.10 mg/g). Conclusions: LASSBio-1386 was effective to prevent RV dysfunction and exercise intolerance indicating important implications for ongoing clinical evaluation of multi-target drugs for the treatment of PAH.

Echocardiographic findings in adult Nigerian sickle cell patients with cardiovascular autonomic dysfunction

Abstract Introduction Involvement of the cardiovascular autonomic nervous system in various diseases is often associated with increased morbidity and mortality. Aim This study was aimed at determining the relationship between cardiovascular autonomic dysfunction (CAD) and echocardiographic indices of cardiac function in adult Nigerian sickle cell anaemia patients. Material and methods A cross sectional study was done using 62 sickle cell anaemia patients and 62 age and sex matched normal controls. CAD was determined based on abnormal values in at least two of five non-invasive tests: Valsalva manoeuver, heart rate variation during deep breathing, heart rate response to standing, blood pressure response to sustained hand grip, and blood pressure response to standing. The subjects were subsequently evaluated with echocardiography. Results and discussion Significant increases in left ventricular posterior wall thickness, left ventricular mass as well as left ventricular mass index were found in patients with CAD. Indices of left ventricular diastolic and systolic functions were comparable in patients with and without CAD, however patients with CAD had lower peak aortic systolic velocity (P = 0.038). Valsalva ratio correlated significantly with right ventricular internal diameter (r = −0.388; P = 0.009), left ventricular posterior wall diameter (r = −0.352; P = 0.019), left ventricular end systolic stress/end systolic dimension ratio (r = 0.512; P Conclusions CAD is a serious complication of sickle cell anaemia. All the patients should be routinely evaluated for CAD.

A New Perspective to Evaluate Doppler Vascular Impedance in Hypertensive Disorders Complicating Pregnancy: Multilevel Modeling Established in a Case Control Study

Background: There have been researches on the evaluation of Doppler vascular impedance in hypertensive disorders complicating pregnancy (HDCP). With respect to the method of analysis used and the conclusions drawn in previous studies, different vessels were usually viewed separately and independently. This study was designed to evaluate Doppler vascular impedance changes in HDCP from a new perspective, with original thought and insight into an ordinary issue. Methods: 273 pregnant women (110 hypertensive pregnancies and 163 normotensive pregnancies) were randomly included in a grouping case-control study conducted from February 10, 2011 to April 30, 2013. All women in the study underwent Doppler measurements of six different vessels including the umbilical artery, the uterine arteries, the placental bed spiral artery, the fetal middle cerebral artery and the fetal renal artery. Doppler vascular impedance was presented as pulsatility index (PI), resistance index (RI), and systolic and diastolic ratio (S/D). Doppler changes in the hypertensive and normotensive groups were assessed by the multilevel modeling approach with univariate and multivariate-adjusted analyses. Results: According to multilevel modeling approach with multivariate-adjusted analysis, a relatively average evaluation on Doppler vascular impedance was provided. Hypertension was significantly associated with positive effects on PI, RI and S/D values (coefficients were 0.10, 0.03 and 0.08, respectively; 95% CIs were 0.06 - 0.14, 0.02 - 0.04 and 0.04 - 0.11, respectively; P values were all less than 0.001) in comparison with normotensive group. Conclusion: According to an overall evaluation, Doppler vascular impedance in hypertensive disorders complicating pregnancy was higher than in normotensive pregnancy. The novel thought and approach applied in this research may bring about inspirations for better understanding and assessment of the disease.

Integration of umbilical venous and arterial Doppler flow parameters for prediction of adverse perinatal outcome

Background: Quantification of umbilical vein (UV) blood flow rate and umbilical artery Doppler indices might be valuable in assessing fetuses at increased risk of perinatal complications as they receive their supply of oxygen and nutrients through this vessel. Previous studies have indicated that UV blood volume flow rate to umbilical artery pulsatility index (UAPI) ratio (venous arterial index [VAI]) evaluates both venous and arterial arm of fetal umbilical circulation and hence, can be adopted as a screening tool in management of high risk pregnancy. Objectives: To compare umbilical VAI with adverse perinatal outcome and also to evaluate its efficacy with other flow indices in determining perinatal outcome. Materials and Methods: Various Doppler indices such as normalized blood flow rate in UV (nUV, ml/kg estimated fetal weight/min), VAI (nUV/UAPI), umbilical artery resistance index (RI), UAPI, and systolic diastolic ratio were determined in 103 pregnant women within 2 weeks of the delivery. A risk score was devised using APGAR at 5 min, birth weight, preterm delivery, fetal distress, Neonatal Intensive Care Unit (NICU) care, and perinatal death and this score was correlated with antenatal Doppler findings. Results: Subjects with low VAI were found to have a greater association with intrauterine growth restricted fetuses (28.5%) and low liquor (35.7%), preterm deliveries (46.4%), lower mean birth weight (2.25 kg), higher NICU admission rates (32.1%). The unfavorable score was noticed in 25.2% of the neonates. They had lower VAI (156 vs. 241), UV diameter (6.2 mm vs. 7.8 mm), UV velocity (16.2 vs. 17.8), nUV (163.7 vs. 206.4), and higher PI (1.3 vs. 0.9). A cut-off of VAI of 105 ml/kg/min had sensitivity of 86.7% and a specificity of 93.5% for predicting poor perinatal outcome. Conclusion: VAI with a cut-off of 105 ml/kg/min can be used as an additional tool along with the other conventional Doppler indices in order to predict adverse fetal outcome.

Abstract 19277: Late Systolic Central Hypertension as a Predictor of Incident Heart Failure: the Multi-Ethnic Study of Atherosclerosis

Background: Experimental studies demonstrate that high aortic pressure in late systole relative to early systole, causes greater myocardial remodeling and dysfunction, for any given absolute peak systolic pressure. Methods: We tested the hypothesis that late systolic hypertension, defined as the ratio of late (last 1/3 of systole) to early (first 2/3 of systole) pressure-time integrals (PTI) of the aortic pressure waveform, independently predicts incident heart failure (HF) in the general population. Aortic pressure waveforms were derived from a generalized transfer function applied to the radial pressure waveform recorded non-invasively from 6,124 adults. The late/early systolic PTI ratio (L/ESPTI) was assessed as a predictor of incident heart failure (HF) during median 8.5 years of follow-up. Results: The L/ESPTI was predictive of incident HF (hazard ratio per 1% increase=1.22; 95%CI=1.15-1.29; P&lt;0.0001) even after adjustment for established risk factors for HF (HR=1.23; 95%CI=1.14-1.32: P&lt;0.0001). In a multivariate model that included brachial systolic and diastolic blood pressure and other standard risk factors of HF, L/ESPTI was the modifiable factor associated with the greatest improvements in model performance. A high L/ESPTI was more predictive of HF than the presence of hypertension. After adjustment for each other and various predictors of HF, the HR associated with hypertension was 1.39 (95%CI=0.86-2.23; P=0.18) whereas the HR associated with a high L/E was 2.31 (95%CI=1.52-3.49; P&lt;0.0001). Cumulative hazard curves for HF among participants stratified according to the presence or absence of hypertension (prevalence=45%) or a high L/ESPTI (set empirically to an identical prevalence of 45% based on E/LSPTI) are shown in the figure. Conclusions: Independently of the absolute level of peak pressure, late systolic hypertension is strongly associated with incident HF in the general population.

Carotid duplex criteria for patients with contralateral occlusion

BackgroundContralateral occlusion (CLO) occurs in approximately 8% of patients undergoing intervention for carotid artery stenosis. Patients with CLO have increased stroke risk compared with patients without CLO, but standard carotid duplex ultrasonography (CDUS) criteria are not a reliable manner to screen or follow patients with CLO. Because appropriate duplex criteria for these patients are not well understood, this article defines CDUS parameters that accurately predict carotid artery stenosis at our institution. MethodsSixty-five patients with ipsilateral carotid stenosis and CLO were identified from our institutional database. Fifteen of sixty-five patients had arteriography, computed tomography angiography, or magnetic resonance angiography within 6 mo of CDUS. We determined accuracy of our laboratory's criteria for determining stenosis category compared with three-dimensional imaging. Receiver operating characteristic curves were used to determine optimal peak systolic velocity (PSV), end diastolic velocity (EDV), and systolic ratio (SR) cutoff values for diagnosing ≥50% stenosis in this pilot cohort. Finally, the revised criteria were prospectively applied to a validation cohort (n = 8) from the same institution. ResultsCategorization of stenosis by standard PSV, EDV, and SR criteria saw similar accuracy trends in both pilot (46.7, 53.3, and 66.7%) and validation (25, 25, and 62.5%) cohorts. Receiver operating characteristic curve analysis in the pilot cohort identified optimized PSV, EDV, and SR cutoffs (≥250, ≥90, and ≥2.3 cm/s, respectively) for diagnosing ≥50% stenosis. In the pilot cohort, new PSV criteria increased specificity (60%–100%) with minimal decreased sensitivity (90%–80%), whereas new EDV criteria increased specificity (40%–71.4%) and maintained 100% sensitivity. New SR criteria failed to improve sensitivity or specificity above 80%. Similar trends for the new CDUS velocity criteria were observed in the validation cohort. ConclusionsIncreasingly stringent ultrasound parameters can provide reliable criteria for determining ≥50% carotid stenosis in patients with CLO. Further prospective validation that includes more patients with high-grade ipsilateral stenosis will help identify the role of SR in segregating high-grade versus moderate stenosis in CLO patients.

Characters available in photoplethysmogram for blood pressure estimation: beyond the pulse transit time.

The continuous and noninvasive blood pressure (BP) measurement based on pulse transit time (PTT) doesn't need cuff and could monitor BP in real time for a long period. However, PTT is just a time index derived from electrocardiogram (ECG) and photoplethysmogram (PPG), while BP-related information within the PPG waveform has seldom been taken into consideration. We hypothesized that PPG waveform feature might be useful for BP estimation. Nine healthy subjects took part in an exercise stress test, including baseline resting, exercise on bicycle ergometry and recovering resting. ECG of lead V5 and PPG from left finger were collected simultaneously, and systolic blood pressure (SBP) and diastolic blood pressure (DBP) were recorded from a cuff sphygmometer on the right wrist. The correlation coefficients were obtained between BP (SBP, DBP and pulse pressure (PP)) and PPG morphological indices (total 15 indices in terms of waveform amplitude, time span and area ratio). Five PPG indices were correlated with both SBP and PP (absolute value of correlation coefficient |r| > 0.6) and were further tested for the capability to BP estimation, which were: (1) PTTA, time delay between the R peak of ECG and the foot point of PPG; (2) RSD, time ratio of systole to diastole; (3) RtArea, area ratio of systole to diastole; (4) TmBB, time span of PPG cycle; (5) TmCA, diastolic duration. Comparisons were made between the measured BP and the estimated BP by regression lines and quadratic curve fitting, respectively. As a result, the mean errors of SBP liner fitting with RSD, RtArea, TmBB and TmCA respectively were 5.5, 5.4, 5.2, 5.1 mmHg, which were smaller than that with PTTA of 5.8 mmHg. And the mean errors of SBP quadratic curve fitting with RSD, RtArea, TmBB and TmCA were all 5.1 mmHg, which were smaller than that with PTTA of 5.7 mmHg. The mean errors of multiple regression for SBP, PP and DBP was 4.7, 4.7, 3.5 mmHg respectively, which were more accurate than the regression with single PTTA of 5.8, 5.3, 5.2 mmHg respectively. However, PPG-based SBP and DBP could under estimate cuff pressure by 8 mmHg and over estimate by 10 mmHg respectively, which is a clinically significant error. In conclusion, the combination of time span (PTT, time ratio of systole to diastole, time span of PPG cycle and diastolic duration) and waveform morphology (area ratio of systole to diastole) could improve the performance of PPG-based BP estimation.

Study Of Sex Differences In Systolic Blood Pressure And Exercise In Non- Athletic Adults

Background & Objectives: The aim of the present study was to study the sex d ifferences in Systolic Blood Pressure (SBP) responses to Exercise in healthy, non- athletic adu lt's. SBP during exercise have been found to predic t hypertension, coronary heart disease and cardiovascular disease (CVD). Materials & Methods: One hundred normal, healthy, non-smoking subjects (50 Male & 50 Female) of Dr. PSIMS& RF are selected based on healthy life style, Body mass index, rest ing blood pressure & resting heart rate. Results: Age, BMI and pre-exercise heart rate showed no significant differences between genders. During the exercise test, males showed extremely si gnificant % rise in SBP & HR than females. % HR decline in 1st min and 3rd min has got extremely statistical significance between males and females. Systolic blood pressure recovery ratio shows extremely significant increase from 1st min to 3rd min in males. The % HR decline in the 3rd min showed extremely significant increase in males when compared to females. SBP responses during and after maximal exercis e were estimated using percentage SBP rise (%SBP rise) and SBP ratio in 3 minutes of recovery relative to 1 minute (SBP R2). Males showed a significantly higher %SBP rise (34.75± 6.32; p<0.00 1) and lower SBPR2 (0.90± 0.04; p<0.001) in comparison to females. Conclusion: Exercise SBP testing provide an important clue to i dentify the subjects at risk for developing hyperte nsion

Estimation of the Functional Condition of a Fetus of Pregnancy in Chronic Pyelonephritis

Aim of this study was to investigate the condition of the fetus and feto placental system in chronic pyelonephritis by identifying features in the fetoplacental blood flow and middle cerebral artery system. We examined 68 pregnant women with chronic pyelonephritis and 50 healthy pregnant women as a control group. The study conducted a qualitative assessment of fetus and placental blood flow and blood flow in the middle cerebral artery of the fetus. The data on the condition of feto-placental blood flow and blood flow in the middle cerebral artery in the examined pregnant and control group show a higher incidence of elevated systolic and diastolic performance ratio in the umbilical artery in patients with chronic pyelonephritis than somatically healthy women. Studies have shown that the most accurate and informative indicator of violations feto-placental circulation is an increase in the umbilical artery whose value (2,9 and above) reflects the high degree of suffering of the fetus on a background of chronic pyelonephritis. Diagnostically significant is the indicator of the middle cerebral artery blood flow, which reflects the mechanism of enhancement of cerebral circulation in chronic hypoxia due to violation of feto-placental circulation in patients with renal disease.

FREQUENCY OF SEVERE CAROTID ARTERY STENOSIS IN DIABETIC PATIENTS HAVING TRIPLE VESSEL CORONARY ARTERY DISEASE

Objective: To determine the frequency of severe carotid artery stenosis in diabetic patients having triple vessel coronary artery disease. Methodology: It was a cross-sectional study conducted from July 2011 to January 2012. Seventy four diabetic patients having triple vessel disease (TVD) were included in the study. Carotid Doppler scan was done in all patients. Severe carotid artery stenosis was diagnosed with the help of Doppler diagnostic criteria that was peak systolic velocity of > 2.3 m/ sec of internal carotid artery (ICA) or peak diastolic velocity of >1.00 m/sec of ICA or ICA/common carotid artery (CCA) systolic ratio of >4 and confirmed by two Radiologist Data was entered on the proforma attached. Results: Out of total 74 patients males were 74% and females were 26%. Their mean age was 56.95 ± 8.77 years. Patients having DM for more than 10 years were 41(55.40%). Mean duration of DM was 9.4±4.8 years.Severe carotid artery stenosis i.e. 70 % stenosis was found in 8 patients (10.8 %) of the study population. Out of these 8 patients right carotid was involved in 5 patients while the remaining 3 patients had stenosis of the left carotid artery. Conclusion: Severe carotid artery stenosis is found in significant number (10.8%) of diabetic patients having triple vessel disease.

Feasibility of initial post-systolic to systolic strain rate ratio as a predictor for viability of the ischemic myocardium with acute ST-elevation myocardial infarction

Purpose: To investigate the strain index of viability on the ischemic myocardium with acute ST-elevation myocardial infarction (STEMI). Methods: Fifty-seven patients with acute STEMI were collected and assessed by 2D speckle-tracking echocardiography strain and strain rate imaging prior to urgent revascularization at acute phase and one year follow-up of post-revascularization. At acute phase, all myocardial segments were divided by their acute end-systolic strain (Ses) into those with normal (Ses; ≤ –13%), hypocontractile (–13% –7%). At the one year of follow-up, we re-assessed the recovery of severe contractile abnormality. Viability of these segments was defined as improved Ses (≤ –7%) after post-revascularization at follow-up. Results: Ses, post-systolic shortening index (PSI) and strain rate (SR) were significantly better in the viable than in the non-viable segments at both acute phase and follow-up (p<0.001). Initial post-systolic to systolic SR ratio (SRps/SRs) had the best AUC 0.897, and a cut-off value of 0.6 predicted recovery from severe contractile abnormality with a sensitivity of 75% and specificity of 88%. View this table: Comparison of accuracy for strain rate parameters Conclusions: Initial SRps/SRs could identify viability for the ischemic myocardium with acute STEMI.

Restricted blood flow in the abdominal aorta at rest and exercise in patients after coarctation aortae repair despite correction

Purpose: Anatomic measurements and blood pressure differences in rest are currently used to determine whether patients after aortic repair for coarctation have a recoarctation or not. Whether flow patterns in the abdominal aorta at rest and during exercise are of additional value in determining functional restriction of the former coarctation side is unknown. Therefore, we investigated Doppler flow patterns in the abdominal aorta compared these with normal volunteers. Methods: We included random patients after aortic coarctation repair without significant re-coarctation on MRI, or uncontrolled hypertension. All patients underwent a rest echocardiography and a bicycle exercise test with echocardiographic examination limited to 70% of the predicted heart rate. Echocardiography was performed according to international recommendations. The systolic diastolic ratio (S/D) was measured in the abdominal aorta. The pulse delay was the difference of the time measured from R-wave until peak velocity in the left ventricular outflow tract and the abdominal aorta. Ten random healthy volunteered controls underwent the similar protocol. Results: Twenty adult patients were included (10 males, mean age 38 years±5) and 10 healthy controls (4 males, mean age 41 years± 10). The maximum flow velocity in the descending aorta was significantly higher than in healthy volunteers. The S/D ratio at rest was similar for both patient groups, but differed significantly at exercise. The pulse delay was significantly larger in coarctation patients than in controls. All parameters indicate a abnormal arterial systemic flow pattern below the coarctation site. View this table: Conclusion: Patients after coarctation without clinical recoarctation have very abnormal flow patterns in the post coarctation aorta, especially during exercise. Further research is needed to determine whether this is clinical meaningful and whether other definitions of recoarctation should be formulized.

Duplex ultrasound interpretation criteria for inferior mesenteric arteries

There is no specific duplex ultrasound (DUS) criteria for the diagnosis of inferior mesenteric artery (IMA) stenosis. This study will define the optimal duplex velocity values with the best overall accuracy (OA) in detecting ≥50% stenosis of the IMAs. Eighty-five IMAs with both DUS and mesenteric arteriography were analyzed. Eighty-five IMAs were examined: 45 were normal, 12 with <50% stenosis, eight with ≥50-69% stenosis and 15 with ≥70% stenosis (including occlusion) based on angiography. The mean peak systolic velocities (PSVs) for a normal IMA, <50% and ≥50% stenosis was 105, 215 and 392 cm/second, respectively (P < 0.0001). The most accurate PSV in detecting ≥50% stenosis was ≥250 cm/second with a sensitivity of 90%, a specificity of 96% and an OA of 95%. The most accurate end-diastolic velocity (EDV) in detecting ≥50% stenosis was ≥80% or ≥90 cm/second, with an OA of 86%, a sensitivity of 60% and a specificity of 100%. The most accurate ratio in detecting ≥50% stenosis was ≥4 or ≥4.5 with an OA of 93%.Receiver operator curves analysis showed that the PSV was not better than EDV and PSV ratio in detecting ≥50% stenosis (P = 0.1661 and 0.4568, respectively). In conclusion, specific IMA PSVs, EDVs and IMA/aortic systolic ratios can be used in detecting significant IMA stenosis with reasonable accuracy.

Noninvasive pressure pulse waveform analysis of flow-mediated vasodilation evoked by post-occlusive reactive hyperemia maneuver

Post-occlusive reactive hyperemia (PORH) assesses flow-mediated vasodilation at microvascular level due to bioactivity of endothelial-derived factors. Ordinary augmentation index that quantifies endothelial response is based on an ensemble-averaged waveform that limits its short-time application. This study proposes a mathematical model and two corresponding indices to evaluate arterial pressure response after blood flow restoration. Radial pressure pulse waveforms were acquired by a 12bits acquisition board at a sampling rate of 1.0kHz using a piezoelectric transducer. Signals were stored during 30s at baseline condition and 60s after 5-min occlusion using an arm-cuff placed over the brachial artery. In both conditions, the pressure pulse waveform presents systolic and diastolic phases with progressive and regressive pulse waveforms, respectively. Changes in pulse wave morphology were also observed and comprised attenuation of the pulse pressure amplitude (markedly first and second systolic peaks). This characteristic of the pulse pressure was described by the time-domain summation of two pairs of Gaussian-like waveforms (representing independent progressive and regressive components) with parameters related to amplitude, time lag, and duration for each component. A steepest descent optimization routine was used to fit the model parameters to experimental data of normotensive and subjects with hypertension. The optimized parameters were used to calculate two indices, RIx1,2 (second-to-first systolic peak ratio) and RIx1,3 (first diastolic-to-first systolic ratio). The observed responses between groups suggest that RIx1,2 is related to an endothelial response to the ischemic process and could be used as a clinical tool to assess endothelial function in hypertension.