Mean Diastolic Flow Velocity Research Articles

Characteristics of coronary flow velocity reserve on transthoracic Doppler echocardiography in patients with a history of Kawasaki disease.

The coronary flow velocity reserve of the left anterior descending artery was examined by transthoracic Doppler echocardiography in 189 patients (male 125, female 64) with a history of Kawasaki disease and 10 volunteers (control). Their ages ranged from 6 to 40 years (median 22 years). The patients were divided into nine groups based on the left anterior descending artery lesions. The coronary flow velocity reserve was measured by intravenous administration of adenosine triphosphate (0.15 mg/kg/minute) while fasting. The coronary flow velocity reserve was calculated as the ratio of hyperaemic to basal mean diastolic flow velocities. The respective groups were as follows: control, no coronary artery lesions (n = 39), no coronary artery lesions in the right coronary artery (n = 29), regression (n = 11), aneurysm at the bifurcation of the left coronary artery (n = 26), aneurysm of the left anterior descending artery (n = 15), localised stenosis <75% (n = 12), localised stenosis ≥75% (n = 17), segmental stenosis (n = 5) and coronary artery bypass grafting (n = 36). One-factor ANOVA followed by Tukey's test was used to compare the coronary flow velocity reserve among the groups. The coronary flow velocity reserve was significantly lower in the localised stenosis ≥75%, segmental stenosis and coronary artery grafting groups than in the other groups (p < 0.05). The endothelial function in the epicoronary artery was preserved in patients with a history of Kawasaki disease and dilated coronary artery lesions.

Assesment of Cerebral Blood Flow Velocities with Transcranial Doppler Ultrasonography in Heart Failure Patients with Reduced Ejection Fraction

BackgroundHeart and brain interaction is a well-known entity in heart failure (HF) and left ventricular systolic dysfunction poses an increased risk for stroke and cognitive impairment. Transcranial Doppler (TCD) provides valuable information on cerebral blood flow velocities (CBFV). However, less is known about CBFV in HF patients with reduced EF. So, we aimed to evaluate CBFV by means of TCD in patients with HF and reduced ejection fraction (HFrEF). MethodsThis study included 46 HFrEF patients (mean age 65.2±11 years, mean EF 20.1±3.8%) who underwent to TCD examination. In addition, 26 healthy individuals with sinus rhythm and EF >50% were included in the study as a control group. Peak systolic, mean and end diastolic flow velocities of the both right and left middle cerebral artery (RMCA and LMCA) were analyzed. In subgroup analysis, HFrEF patients compared according to rhythm. Correlation analyses was performed in HFrEF group between EF and TCD velocities. ResultsThe average of RMCA and LMCA peak systolic and mean flow velocities were significantly lower in HF patients than those in control group (76,06±23,7 cm/s and 48,49±16,4 cm/s in HF group vs 87,84±14,5 cm/s and 56,41±10,7 cm/s in control group, p=0,025 and p=0,016, respectively, for RMCA and 75,1±22,3 cm/s and 47,57±14.8 cm/s in HF group vs 88,73±17,7 cm/s and 57,15±12,4 cm/s in control group, p=0,009 and p=0,007, respectively, for LMCA). The average mean flow velocity of RMCA and LMCA was significantly lower in HFrEF patients with AF than HFrEF patients with sinus rhythm. (P=0.04 and P= 0.03, respectively) In correlation analysis, EF was significantly positively correlated with both LMCA and RMCA flow velocities in HFrEF group. ConclusionThis study showed that HFrEF patients have lower CBFV as compared to healthy controls and HFrEF patients with AF rhythm have lower CBFV compared to HFrEF with sinus rhythm which might be one of the explanations of the adverse interaction between heart and brain in HFrEF.

P4432Coronary microvascular dysfunction in inflammatory bowel disease: Restored after enterectomy

Abstract Background Inflammatory bowel disease (IBD) is a complex multisystem disease characterized by chronic inflammation, which can lead to coronary microvascular dysfunction (CMD). Purpose We aimed to investigate the presence and the severity of CMD in Crohn's disease (CD) and ulcerative colitis (UC) by assessing coronary flow reserve (CFR) using transthoracic Doppler echocardiography, and to elucidate the influence of enterectomy on CMD. Methods Thirty-seven IBD patients (22 CD patients: 39±12 years, 15 UC patients: 52±17 years), and 30 age- and gender-matched control subjects (46±12 years) who have comparable risk factors for coronary artery disease were enrolled. Smokers were excepted from the present study. For CFR measurement, coronary flow velocity was recorded at rest and during hyperemia in the left anterior descending coronary artery induced by intravenous infusion of adenosine triphosphate (0.14 mg/kg/min), and a CFR ≤2.5 calculated as the ratio of hyperemic to basal peak and mean diastolic velocity defined CMD. CFR measurement was repeated before and within 1 year after enterectomy. Serum or plasma cytokines were also measured before and after enterectomy. Results The median disease duration of CD and UC patients were 12 and 6 years. Although none of control subjects had CMD, 38% in IBD patients (CD: 41%, UC: 33%) had CMD. CFR was similarly and significantly lower in CD and UC patients than Control subjects (CD: 2.92±1.03*, UC: 2.99±0.65*, and Control: 3.84±0.75, *p&lt;0.05 vs. Control). Serum levels of TNF-α, IL-6 and hs-CRP were significantly higher in CD and UC patients than Control subjects. Multiple linear regression analysis showed that the presence of IBD and mean diastolic flow velocity at baseline were independently associated with reduced CFR among all study participants (β=−0.324 and −0.614, p=0.001, respectively). CFR in IBD patients with both CMD and non-CMD significantly improved after enterectomy, and the extent of CFR improvement was greater in patients with CMD than those with non-CMD (Figure). Serum levels of IL-6 and hs-CRP significantly reduced among all IBD patients. Conclusion IBD was associated with CMD, which improved after enterectomy.

Superior vena cava-right atrium junction flow-pattern post-transcatheter closure of patent foramen ovale.

The patent foramen ovale (PFO) occluder is a bulky metallic device. Its impact on the normal blood flow at the superior vena cava-right atrial (SVC-RA) junction is not clear. We examined SVC-RA junction flow-pattern using pulsed-wave (PW) ultrasound Doppler in 21 patients (4 male, aged 52.7±9years) who underwent PFO device closure 4-120months previously, in comparison with 21 age- and sex-matched controls (4 male, aged 51±8.5years) with structurally normal hearts. Mean systolic flow velocity at the SVC-RA junction was 60±11cm/s in the PFO closure group and 64±17cm/s in the control group (P=0.27). Mean diastolic blood flow velocity at the SVC-RA junction in those groups was 30±8 and 35±9cm/s, respectively (P=0.1).The mean systolic wave duration was 439±52ms in the PFO closure group and 422±67ms in the control group (P=0.4). The mean diastolic wave duration was 320±75 and 277±88ms, respectively (P=0.12). The study results show that transcatheter PFO closure does not affect the normal blood flow at the SVC-RA junction.

Fluid Resuscitation in Septic Patients Improves Systolic but not Diastolic Middle Cerebral Artery Flow Velocity

To investigate the effects of fluid resuscitation on cerebral hemodynamics in sepsis, the following set of transcranial Doppler (TCD) parameters was used: maximal change in flow velocity (FV) during stroke onset (acc), maximal FV during first (sys1) or second (sys2) phase of systole and mean diastolic FV (dias@560). We aim to evaluate changes in cerebral hemodynamics that result from (i) sepsis and (ii) adequate fluid resuscitation in critically ill septic patients. In the majority of 16 septic patients sys2 was initially absent but reappeared during the period of fluid resuscitation; whereas sys2 absence was never seen in healthy controls. Second, adequate fluid resuscitation resulted in a significant increase of the systolic FV components (acc, sys1, sys2 and systolic blood pressure); whereas the diastolic components (dias@560 and diastolic blood pressure) remained unchanged. Sys2 absence and reappearance in sepsis suggests that TCD could become a non-invasive alternative for hemodynamic monitoring.

Doppler Sonography of Blood Flow Velocity in the Vertebral Arteries of Preterm and Term Neonates.

This study aimed to evaluate normal blood flow in the vertebral arteries and the basilar artery of preterm and term neonates by Doppler sonography. Blood flow in both vertebral arteries and the basilar artery was examined in 102 neonates between the biological ages of 28 and 41 weeks. Fifty-one boys and 51 girls underwent Doppler sonography. Measurements were usually undertaken at 6 days old. Systolic and diastolic flow velocities, including the resistive index, were measured and analyzed, taking into consideration biological age, weight, and sex. Anatomic aberrations of the vertebral arteries were recorded. Mean blood flow values ± SD in the basilar artery were 35.2 ± 7.4 cm/s (systolic velocity) and 10.9 ± 3.5 cm/s (diastolic velocity). Mean blood flow values in the right vertebral artery were 26.8 ± 9.3 cm/s (systolic velocity) and 8.0 ± 3.7 cm/s (diastolic velocity). Mean blood flow values in the left vertebral artery were 28.6 ± 8.3 cm/s (systolic velocity) and 8.7 ± 3.3 cm/s (diastolic velocity). Systolic and diastolic blood flow in both vertebral arteries was significantly higher from 38 to 41 weeks compared with 28 to 32 and 33 to 37 weeks (P < .05). Regression analysis of systolic and diastolic blood flow velocities in the vertebral arteries versus biological age yielded significant results (P < .05). Sonography is an excellent tool for examining blood flow in the basilar and vertebral arteries of premature and term neonates. Mean systolic and diastolic blood flow velocities in the vertebral arteries increase significantly with age.

Carotid Doppler blood flow measurement during cardiopulmonary resuscitation is feasible: A first in man study

ObjectiveHigh quality chest compressions are the cornerstone of effective cardiopulmonary resuscitation (CPR). There is no available method of real time noninvasive hemodynamic measurement and feedback to inform rescuers of the efficacy of compressions. Ultrasound-based measures of blood flow may provide immediate, noninvasive hemodynamic information. Our objective was to determine the feasibility and safety of using ultrasound to measure blood flow on patients with cardiac arrest. MethodsStudy design This was a prospective cohort study in an emergency department setting. Subjects Included were patients receiving ongoing manual chest compressions for cardiac arrest. Excluded were those less than 18 years of age, incarcerated, pregnant, with neck injury, or obvious traumatic cause of arrest. Scan protocol Physicians recorded blood flow over the common carotid arteries during chest compressions with transverse and longitudinal color flow and Doppler using a portable ultrasound machine (CX30, Philips Healthcare., Andover, MA). Measurements Duration of scan time, and the median values for peak systolic (PSV), end-diastolic (EDV) and mean diastolic (MDV) carotid blood flow velocities were captured. Feasibility was defined as the proportion of eligible subjects upon whom ultrasound was initiated Safety was defined as availability of at least 5min of scanning time. ResultsNineteen patients (56% of eligible) where enrolled and had ultrasound measurements attempted during manual compressions. In one patient, scanning was not initiated because ongoing CPR efforts were terminated. Three patients were enrolled but had no images available for review. A total of 15 patients (78% of attempted) had ultrasound imaging saved. Most (n=10, 66%) had scanning times greater than 5min (median 5min 59s, interquartile range 3min 15s to 8min 25s), median PSV was 67cms−1 (IQR 55–106), median EDV was 18cms−1 (IQR 12–27), and median MDV was 14cms−1 (IQR 9–18). ConclusionsUltrasound measurement of common carotid artery blood flow during CPR is feasible. Further studies are necessary to correlate carotid blood flow to other hemodynamic measures and its effects on patient outcomes.

Coronary Flow Reserve Impairment in Apical vs Asymmetrical Septal Hypertrophic Cardiomyopathy

Mechanisms underlying a reduction in coronary flow reserve (CFR) in hypertrophic cardiomyopathy (HCM), especially apical HCM (ApHCM), are elusive. This study set out to evaluate mechanisms underlying a reduction in CFR in 2 HCM subtypes. Mechanisms for CFR reduction in HCM are different between the 2 subtypes of HCM. Thirty-one patients with asymmetrical septal hypertrophy (ASH), 43 with ApHCM, and 27 healthy volunteers were recruited. Mean diastolic coronary flow velocity (CFmv) was monitored before and after adenosine infusion by transthoracic echocardiography in the mid-to-distal left anterior descending coronary artery. Coronary flow reserve was defined as the ratio between CFmv before and after adenosine infusion. Left ventricular mass index and stress myocardial perfusion were assessed by cardiac magnetic resonance imaging. Although basal CFmv was higher in ASH patients than in healthy controls (P<0.05), it was similar in ApHCM patients and controls (P=0.85). Poststress CFmv was significantly lower in both HCM subtypes than in controls (P<0.05). Consequently, CFR was higher in controls than in ASH or ApHCM patients (P<0.05). When HCM patients were stratified into 2 groups based on the presence of CFR impairment, no difference was observed between these 2 groups in terms of left ventricular mass index by cardiac magnetic resonance imaging. Multivariate logistic regression analysis identified basal CFmv as the only independent variable associated with CFR reduction in HCM (r2=0.49, P<0.001). Whereas the inability to augment coronary flow to its maximal level during stress was found to underlie CFR impairment in both HCM subtypes, the recruitment of vasodilatory capacity at baseline was more prominent in ASH than in ApHCM patients.

Preliminary observations of passive exercise using whole body periodic acceleration on coronary microcirculation and glucose tolerance in patients with type 2 diabetes

BackgroundThe whole body periodic acceleration (WBPA) system was recently developed as a passive exercise device by providing increased pulsatile shear stress for improvement of endothelial function. This study aimed to investigate the acute effects of WBPA on coronary microcirculation and glucose tolerance in patients with type 2 diabetes (T2D). MethodsThe study subjects were 8 patients with T2D who underwent transthoracic Doppler echocardiography for the assessment of coronary flow reserve (CFR) before and immediately after a 45-min session of WBPA. The flow velocity in the distal portion of the left anterior descending coronary artery was measured at baseline and during adenosine infusion. The CFR represented the ratio of hyperemic to basal mean diastolic flow velocity. ResultsWBPA increased CFR from 2.3±0.3 to 2.6±0.4 (p=0.02). WBPA decreased serum insulin level from 26±19μIU/ml to 19±15μIU/ml (p=0.01) and increased total adiponectin from 11.6±7.3μg/ml to 12.5±8.0μg/ml (p=0.02) and high molecular weight adiponectin from 4.9±3.6μg/ml to 5.3±3.9μg/ml (p=0.03), whereas the serum glucose level was stable from 207±66mg/dl to 203±56mg/dl (p=0.8). ConclusionsThis study demonstrates that a single session of WBPA treatment simultaneously improved coronary microcirculation and glucose tolerance in patients with T2D.

Analysis of coronary flow haemodynamics in homozygous familial hypercholesterolaemic adolescents with aortic supravalvular stenosis

To study coronary artery haemodynamics in adolescents with homozygous familial hypercholesterolaemia and aortic supravalvular stenosis. Patients diagnosed with familial hypercholesterolaemia who were younger than 16 years and who had undergone transthoracic echocardiography from 2007 to 2010 were included in this study. We included patients with homozygous familial hypercholesterolaemia and aortic supravalvular stenosis and those with heterozygous familial hypercholesterolaemia. All patients underwent stress echocardiography, and left anterior descending coronary artery flow was successfully detected. Coronary flow velocity reserve was calculated as the ratio of hyperaemic mean diastolic flow velocity after injection of adenosine to basal mean diastolic flow velocity. Changes in coronary haemodynamics and the relationship between lipid concentrations were determined. A total of 11 patients with homozygous familial hypercholesterolaemia were enrolled in this study. Lipid concentrations were measured, and the mean coronary flow velocity reserve was 1.97 plus or minus 0.51. Seven children were included in the group of patients with heterozygous familial hypercholesterolaemia. In these children, the mean coronary flow velocity reserve was 3.08 plus or minus 0.84. The coronary flow velocity reserve of homozygous familial hypercholesterolaemic patients is lower than that of heterozygous familial hypercholesterolaemic patients, and it is associated with a high concentration of low-density lipoprotein cholesterol. Aortic stenosis and plaques compromised the ostia of the coronary artery and caused increased basal mean diastolic coronary velocity with blunted increase in peak velocity, which decreased the coronary flow velocity reserve.

Improved Parameterization of the Transcranial Doppler Signal

The great potential of transcranial Doppler (TCD) as a tool for neuromonitoring is limited by the current parameterization of the signal. This article proposes a set of new parameters that more accurately represents the shape of the waveform and eliminates a number of confounding factors. This set of parameters was tested in 227 patients with ipsilateral carotid artery stenosis and compared with 31 normal subjects recruited at our laboratory. From the TCD waveform, we calculated on a beat-to-beat basis the maximal change in flow velocity at stroke onset (acceleration or acc), the maximal flow velocity during the first 100 ms of systole (sys1) and the maximal flow velocity in the remaining part of systole (sys2). All data were normalized relative to the mean diastolic flow velocity over an interval ranging from 520 till 600 ms after stroke onset (dias@560). For the group with carotid stenosis compared with the normal controls the average ± SD for acc (20.2 ± 9.5 vs. 20.2 ± 6.7; p = 0.98) and sys1 (1.82 ± 0.38 vs. 1.77 ± 0.56; p = 0.35) did not differ significantly. The average ±SD for sys2 (1.94 ± 0.33 vs. 1.50 ± 0.12; p < 0.001), however, was significantly higher in the group with carotid stenosis than in the group of normal subjects. The difference between sys1 and sys2 (“sys1–sys2”) was lower in the patient group than in controls (−0.12 ± 0.16 vs. 0.27 ± 0.22; p < 0.001). For the acc, there was a significantly higher variance in the group with stenosis than without (p < 0.001). Of the old parameters, the beat-to-beat mean (37.0 ± 13.1 vs. 41.3 ± 15.9; p = 0.17) and the pulsatility index (PI; 1.00 ± 0.26 vs. 0.91 ± 0.23; p = 0.06) were not significantly different between groups. Graphed together the acc and “sys1–sys2” parameters allowed a clear demarcation of both groups whereas in a graph of the old parameters mean and PI both groups overlapped considerably. In conclusion, the proposed set of new parameters not only has theoretical and practical benefits but also has excellent discriminative power in a group of carotid patients compared with normal controls.

Comparison of Coronary Microcirculation in Female Nurses After Day-Time Versus Night-Time Shifts

Nightshift work, which is known to cause mental stress and disrupt normal biological diurnal rhythms, leads to endothelial dysfunction resulting in increased risk for cardiovascular disease. This study aimed to investigate the acute effect of night-shift work on coronary microcirculation through assessment of coronary flow reserve (CFR) by transthoracic Doppler echocardiography. This study consisted of 36 women nurses who underwent transthoracic Doppler echocardiographic examinations after working a nightshift and on a regular day without previous nightshift work. Flow velocity in the distal portion of the left anterior descending coronary artery was measured at baseline and during adenosine infusion. CFR was calculated as the ratio of hyperemic to basal mean diastolic flow velocity. CFR after night work was lower than that on a regular workday (3.8 ± 0.6 vs 4.1 ± 0.6, p <0.001). Degree of decreases in CFR after night work was correlated to Framingham risk score (r = 0.35, p = 0.036). In conclusion, this study demonstrated that coronary microcirculation was impaired after nightshift work in women nurses.

Assessment of Coronary Flow Velocity Reserve by Transthoracic Doppler Echocardiography Before and After Coronary Artery Bypass Grafting

Little is known about the changes in the coronary flow velocity reserve (CFVR) of the left anterior descending artery (LAD) before and after coronary artery bypass grafting (CABG). The present study aimed to evaluate the feasibility of measuring the CFVR of the LAD using transthoracic Doppler echocardiography before and after CABG. We prospectively measured the CFVR before and after CABG in 56 patients. The flow velocity in the LAD was measured using transthoracic Doppler echocardiography both at rest and during intravenous infusion of adenosine. The CFVR was calculated as the ratio of hyperemic to the basal peak and mean diastolic flow velocities. Coronary angiography was also performed to assess graft patency after CABG in all patients. Furthermore, we compared the differences between the pre- and postoperative CFVR in patients with and without a diffusely diseased LAD (lesion length >2 cm). All grafts were angiographically patent. The postoperative peak and mean CFVR were significantly increased compared to the preoperative peak and mean CFVR (both peak and mean 2.7 ± 0.9 vs 1.5 ± 0.6, respectively; p<0.0001). The preoperative peak CFVR was significantly lower in patients with a diffusely diseased LAD than in those without a diffusely diseased LAD (1.3 ± 0.5 vs 1.6 ± 0.5, respectively; p=0.04). The postoperative peak CFVR of the 2 groups was almost identical (2.5 ± 0.6 vs 2.9 ± 1.0; p=0.07). In conclusion, assessment of the CFVR of the LAD using transthoracic Doppler echocardiography was useful after CABG for confirming graft patency.

Estimation of Coronary Flow Velocity Reserve Using Transthoracic Doppler Echocardiography and Cold Pressor Test Might Be Useful for Detecting of Patients with Variant Angina

The cold pressor test (CPT) has been used to detect variant angina, but its sensitivity in predicting vasospasm is low. The aim of this study was to determine whether estimates of the coronary flow velocity reserve (CFVR) in the distal left anterior descending coronary artery (dLAD) using transthoracic echocardiography (TTE) and CPT are useful tool to predict variant angina. 65 patients (mean age = 52 +/- 10 years; male:female = 41:24) who had normal coronary artery on angiography and underwent acetylcholine provocation test were enrolled and divided into the spasm group (n = 31) and the no spasm group (n = 34). During CPT, the peak (PDV) and mean diastolic flow velocity (MDV) of the dLAD were estimated using TTE with a high-frequency transducer, and electrocardiography, blood pressures, heart rate, and symptoms were monitored every 30 seconds. CPT%PDV and CPT%MDV were defined as the percentage changes in PDV and MDV during CPT, respectively. CPT%PDV was 4.99 +/- 23.62% in the spasm group and 52.75 +/- 24.78% in the no spasm group (P < 0.001). CPT%MDV was 6.83 +/- 23.81% in the spasm group and 50.22 +/- 27.83% in the no spasm group (P < 0.001). CPT%PDV<31.1% had a sensitivity of 93.5% and a specificity of 82.4% in predicting variant angina (95% confidence interval [CI]: 0.939-0.979, P < 0.001). CPT%MDV<30.55% had a sensitivity of 90% and a specificity of 76.5% in predicting variant angina (95% CI: 0.884-0.950, P < 0.001). The measurement of changes in the coronary flow velocity of the dLAD using TTE and CPT might be useful for the estimation of endothelial dysfunction in patients with variant angina.

A Transthoracic Echocardiographic Follow-Up Study After Catheter Ablation of Atrial Fibrillation: Can We Detect Pulmonary Vein Stenosis by Transthoracic Echocardiography?

Background and ObjectivesWhile pulmonary vein isolation (PVI) is an effective curative procedure for patients with atrial fibrillation (AF), pulmonary vein (PV) stenosis is a potential complication which may lead to symptoms that are often unrecognized. The aim of this study was to compare differences between ablation sites in pulmonary venous flow (PVF) measured by transthoracic Doppler echocardiography (TTE) before and after PVI.Subjects and MethodsOne hundred five patients (M : F=64 : 41; mean age 56±10 years) with paroxysmal AF (n=78) or chronic, persistent AF (n=27) were enrolled. PVI strategies consisted of ostial ablation (n=75; OA group) and antral ablation using an electroanatomic mapping system (n=30; AA group). The ostial diameter was estimated by magnetic resonance imaging (MRI) in patients with PVF ≥110 cm/sec by TTE after PVI.ResultsNo patient complained of PV stenosis-related symptoms. Changes in mean peak right PV systolic (-6.7±28.1 vs. 10.9±25.9 cm/sec, p=0.038) and diastolic (-4.1±17.0 vs. 9.9±25.9 cm/sec, p=0.021) flow velocities were lower in the AA group than in the OA group. Although the change in mean peak systolic flow velocity of the left PV before and after PVI in the AA group was significantly lower than the change in the OA group (-13.4±25.1 vs. 9.2±22.3 cm/sec, p=0.016), there was no difference in peak diastolic flow velocity. Two patients in the OA group had high PVF velocities (118 cm/sec and 133 cm/sec) on TTE, and their maximum PV stenoses measured by MRI were 62.5% and 50.0%, respectively.ConclusionPV stenosis after PVI could be detected by TTE, and PVI by antral ablation using an electroanatomic mapping system might be safer and more useful for the prevention of PV stenosis.

Transient impairment of coronary flow reserve in tako-tsubo cardiomyopathy is related to left ventricular systolic parameters

Recent studies suggest that coronary flow reserve (CFR) is transiently impaired in tako-tsubo cardiomyopathy (TTC). Mechanisms by which such impairment occurs are still unknown. To assess the relationship between CFR obtained by transthoracic Doppler echocardiography (TDE) and parameters of left ventricular (LV) performance in patients with TTC. A total of 20 consecutive patients in sinus rhythm, with TTC (mean age 70+/-9 years, 19 women) underwent serial evaluation of TDE-CFR, in the distal part of the left anterior descending coronary artery (LAD), at the acute phase and after recovery using intravenous adenosine infusion (140 microg/kg/min over 2 min). CFR was calculated as hyperaemic to basal mean diastolic coronary flow velocity (CFV). Average of the septal and lateral mitral annulus early diastolic (Ea) and systolic (Sa) tissue velocity, early (E) and late (A) diastolic transmitral velocity, the ratio E/Ea, wall motion score (WMS, 16 segment model), LV end-systolic volume index (ESV/m(2)) and LV end-diastolic volume index (EDV/m(2), biplane-Simpson method) were serially measured by TDE. Basal CFV, LV mass index and haemodynamics parameters did not differ between acute phase and recovery, whereas hyperaemic CFV increased significantly after recovery (P<0.01) leading to a greater CFR (2.9+/-0.3 vs. 2.1+/-0.4, P<0.0001). At the acute phase, hyperaemic CFV was significantly correlated to WMS, ESV/m(2), but not to E/Ea, whereas at recovery, hyperaemic CFV was not correlated to LV parameters. The improvement of CFR was closely correlated to the decrease of ESV/m(2), of WMS, but not to diastolic parameters. No significant correlation was found between CFR and E/Ea or LV mass index at each stage. There is a transient impairment of CFR at the acute phase of TTC, which is due to a reduced vasodilating capacity. This impairment is closely correlated to LV systolic parameters. Diastolic compressive forces to the coronary microcirculation do not appear to play a critical role.

Diagnosis of Coronary Restenosis Using Coronary Flow Reserve Measurements Obtained Through Transthoracic Doppler Echocardiography

Background and Objectives: Coronary flow reserve (CFR) decreases in the presence of significant coronary stenosis. Hence, CFR can be used for the detection of restenosis after percutaneous coronary intervention (PCI). However, because CFR can also be affected by other conditions such as endothelial dysfunction, microvascular damage, and left ventricular hypertrophy, the absolute value of CFR is not routinely used for detection of coronary restenosis. We hypothesized that changes in the value of CFR, rather than the absolute CFR value, are better correlated with restenosis in various clinical settings. Subjects and Methods: We studied 99 patients (71 males/28 females, mean age 58±11 years) who underwent successful PCI of the left anterior descending artery. Pre-PCI diagnoses were as follows: 37 unstable angina, 35 stable angina, 27 acute myocardial infarction. CFR using transthoracic Doppler was measured at 48 hours after PCI and at the time of follow-up angiography (6.0±1.5 months later). Coronary flow velocity was measured in the distal left anterior descending artery with a 7 MHz transducer (HDI 5,000, Philips, The Netherlands) at baseline and during intravenous infusion of adenosine (140 μg·kg-·min-). Mean diastolic coronary flow velocities from at least three cardiac cycles were averaged. Results: CFRs in 69 patients without restenosis were 2.55±0.99 at 48 hours after PCI and 2.93±1.00 at follow-up (p 50% in diameter stenosis) decreased significantly from 2.70± 1.01 at 48 hours after PCI to 1.98±0.91 at follow-up (p<0.001). There was a significant difference in CFR change (ratio of CFRfollowup/CFRinitial) between the two groups. CFR change had a better receiver operating characteristics (ROC) curve than absolute CFR for prediction of restenosis [area under the curve (AUC) for absolute CFR= 0.76, AUC for CFR change=0.82]. Conclusion: Restenosis after PCI leads to a significant decrease in CFR, even in the presence of variable baseline CFR values. Serial measurements of CFR can be used to detect restenosis after PCI. (Korean Circ J 2008;38:325-330)

Relaxation effects of lavender aromatherapy improve coronary flow velocity reserve in healthy men evaluated by transthoracic Doppler echocardiography

PurposeIt has been reported that mental stress is an independent risk factor for cardiovascular events and impairs coronary circulation. Lavender aromatherapy, one of the most popular complementary treatments, is recognized as a beneficial mental relaxation therapy. However, no study has examined the effect of this therapy on coronary circulation. We aimed to assess the effect of lavender aromatherapy on coronary circulation by measuring coronary flow velocity reserve (CFVR) with noninvasive transthoracic Doppler echocardiography (TTDE). Material and methodsWe enrolled 30 young healthy men (mean age 34±4.7 years, range 24–40 years). Coronary flow velocities in the left anterior descending coronary artery were recorded by TTDE at rest and during hyperemia induced with an intravenous infusion of adenosine triphosphate (ATP). CFVR was calculated as the ratio of hyperemic to basal mean diastolic flow velocity. CFVR was assessed at baseline and immediately after lavender aromatherapy (four drops of essential oil diluted with 20 ml of hot water and inhaled for 30 min). Simultaneously, serum cortisol was measured as a marker of stress hormones. To exclude the relaxation effects of rest, the same measurements were repeated in the same volunteers without aromatherapy as a control study. ResultsCFVR measurements were obtained in all volunteers (100%). Blood pressure and heart rate responses to ATP infusion were not affected by lavender aromatherapy. Serum cortisol significantly decreased after lavender aromatherapy (8.4±3.6 to 6.3±3.3, p<0.05), but remained unchanged in controls (9.1±3.5 to 8.1±3.9, p=ns). In addition, CFVR significantly increased after lavender aromatherapy (3.8±0.87 to 4.7±0.90, p<0.001), but not in controls (3.9±0.8 to 3.9±0.8, p=ns). ConclusionsLavender aromatherapy reduced serum cortisol and improved CFVR in healthy men. These findings suggest that lavender aromatherapy has relaxation effects and may have beneficial acute effects on coronary circulation.

The Coronary Flow Reserve Is Transiently Impaired in Tako-Tsubo Cardiomyopathy: A Prospective Study Using Serial Doppler Transthoracic Echocardiography

The clinical features of tako-tsubo cardiomyopathy or transient left apical ballooning syndrome (LABS) have been clearly described, but the mechanisms are still unknown. Our objective was to prospectively assess coronary microcirculation at the acute phase of LABS and after functional recovery, using Doppler transthoracic echocardiography-coronary flow reserve (CFR). Twelve consecutive patients (11 women, mean age 68 +/- 10 years) satisfying the criteria for LABS underwent Doppler transthoracic echocardiography-CFR in the distal part of the left anterior descending coronary artery, using intravenous adenosine infusion (0.14 mg/kg/min over 2 minutes) at the acute phase and 25 +/- 3 days later. CFR was calculated as the ratio of hyperemic to basal mean diastolic flow velocity. Wall-motion score (WMS) was calculated using the 16-segment model during the same echocardiographic examination (normal WMS = 16). Doppler transthoracic echocardiography-CFR increased between the two examinations from 2.2 +/- 0.4 at the acute phase to 2.9 +/- 0.3 (P < .01), whereas WMS decreased (from 31 +/- 6 at the acute phase to 16.5 +/- 0.8, delta WMS = -14.6 +/- 6, P < .01). All patients exhibited an increase of CFR between the two tests (delta CFR = 0.73 +/- 0.39, range: 0.3-1.6). A significant correlation was observed between delta CFR and delta WMS (r = -0.89, P < .01). In conclusion, serial noninvasive CFR measurements performed in LABS suggested transient microcirculatory impairment during the acute phase of the syndrome. The wall-motion improvement parallel to the dynamic improvement of the microcirculation suggests a role of coronary microcirculatory damage in the pathogenesis of acute and transient wall-motion abnormalities in LABS.

Diurnal Variation in Coronary Flow Velocity Reserve in Healthy Men

Background. A number of cardiovascular diseases show diurnal variation. However, it is unknown whether coronary circulation exhibits diurnal variation.Methods. The flow velocities in the left anterior descending coronary artery of 15 healthy men were measured by transthoracic Doppler echocardiography both at rest and during intravenous infusion of adenosine triphosphate at 7 AM, noon, 5 PM and 9 PM. Coronary flow velocity reserve (CFVR) was calculated as the ratio of hyperemic to basal mean diastolic flow velocity. CFVR at 7 AM was significantly smaller than that at 9 PM (p=0.001; 7 AM, 3.23 ± 0.66; noon, 3.89 ± 0.86; 5 AM, 3.46 ± 0.65; 9 PM, 4.41 ± 1.11, respectively). CFVR at 5 PM was also significantly smaller than that at 9 PM (p=0.008).Conclusions. Diurnal variation in CFVR exists in healthy men. This finding may be related to the diurnal variation in cardiovascular events.