Quantitative myocardial perfusion in liver transplantation candidates: Poorly metabolized caffeine inhibition of vasodilatory stress.

BACKGROUND: Data on cardiac positron emission tomography (PET) in liver transplantation (LT) candidates are limited with no prior study accounting for poorly metabolized caffeine reducing stress perfusion. METHOD: Consecutive LT candidates (n = 114) undergoing cardiac rest/stress PET were instructed to abstain from caffeine for 2 days extended to 5 and 7 days. Due to persistently high prevalence of measurable blood caffeine after 5-day caffeine abstinence, dipyridamole (n = 41) initially used was changed to dobutamine (n = 73). Associations of absolute flow, coronary flow reserve (CFR), detectable blood caffeine, and Modified End-Stage Liver Disease (MELD) score for liver failure severity were evaluated. Coronary flow data of LT candidates were compared to non-LT control group (n = 102 for dipyridamole, n = 29 for dobutamine). RESULTS: Prevalence of patients with detectable blood caffeine was 63.3%, 36.7% and 33.3% after 2-, 5- and 7-day of caffeine abstinence, respectively. MELD score was associated with detectable caffeine (odd ratio 1.18,P < 0.001). CFR was higher during dipyridamole stress without-caffeine versus with-caffeine (2.22 ± 0.80 vs 1.55 ± 0.37,P = 0.048) but lower than dobutamine stress (2.22 ± 0.80 vs 2.82 ± 1.02,P = 0.026). Mediation analysis suggested that the dominant association between CFR and MELD score in dipyridamole group derived from caffeine-impaired CFR and liver failure/caffeine interaction. CFR in LT candidates was lower than non-LT control population in both dipyridamole and dobutamine group. CONCLUSION: We demonstrate exceptionally high prevalence of detectable blood caffeine in LT candidates undergoing stress PET myocardial perfusion imaging resulting in reduced CFR with dipyridamole compared to dobutamine. The delayed caffeine clearance in LT candidates makes dobutamine a preferred stress agent in this population.

Prognostic significance of dobutamine stress echocardiography in patients with chronic kidney disease and known or suspected coronary artery disease: a 5-year follow-up study.

Dobutamine stress echocardiography (DSE) is an effective noninvasive modality for evaluating coronary artery disease (CAD), with high accuracy. However, data on the prognostic value of DSE in patients with chronic kidney disease (CKD) are limited. This study aims to assess the prognostic significance of DSE in patients with CKD and known or suspected CAD. We included consecutive patients with CKD stage 3 or higher and known or suspected CAD who underwent clinically indicated DSE between 2007 and 2017. The primary endpoint was all-cause mortality at 5 years. Univariable and multivariable analyses were conducted to identify predictors of all-cause mortality, with a p value < 0.05 considered statistically significant. A total of 274 patients were included in the study. The mean age was 64.0 ± 13.1 years, with 54% being male and 13.1% having known CAD. Among the patients, 64.6% had advanced CKD (≥ stage 4). Abnormal DSE was observed in 62 patients (22.6%). During a follow-up period of 7.0 ± 3.5 years, 78 patients (28.5%) died. The mortality rate was significantly higher in patients with abnormal DSE compared to those with normal DSE (48.4% vs. 22.6%, p < 0.001). Multivariable analysis identified age (hazard ratio [HR] 1.03, 95% confidence interval [CI] 1.008-1.05, p = 0.005), New York Heart Association (NYHA) functional class (HR 1.60, 95% CI 1.05-2.43, p = 0.03), and chronotropic index < 0.73 (HR 2.61, 95% CI 1.60-4.25, p < 0.001) as independent predictors of mortality. Conversely, a normal DSE result was found to be a protective factor (HR 0.49, 95% CI 0.30-0.81, p = 0.005). In conclusion, DSE demonstrated significant prognostic value in patients with CKD and known or suspected CAD. Age, NYHA functional class, and a chronotropic index < 0.73 were identified as independent predictors of all-cause mortality.

Three-dimensional anatomic features of the mitral valve that predict systolic anterior motion occurring during dobutamine stress echocardiography.

BACKGROUND/AIM: Left ventricular outflow tract obstruction related to systolic anterior motion (SAM) of the mitral valve is a common complication of dobutamine stress echocardiography (DSE). However, the mechanisms underlying SAM have not been fully characterized. The objective of the present study was to use three-dimensional echocardiography to identify anatomic features of the mitral valve that predispose to SAM during DSE. METHODS: We retrospectively evaluated consecutive patients included prospectively in our database and who had undergone 3D echocardiography (including an assessment of the mitral valve) before DSE. Patients who had developed SAM during DSE (the SAM+ group) were matched 2:3 with patients who did not (the SAM- group). RESULTS: One hundred patients were included (mean age: 67 ± 10). Compared with SAM- patients (n = 60), SAM+ patients (n = 40) had a lower mitral annular area, a smaller perimeter, and a smaller diameter (p < .01 for all, except the anteroposterior diameter). The SAM+ group had also a narrower mitral-aortic angle (126 ± 12° vs. 139 ± 11° in the SAM- group; p < .01) and a higher posterior mitral leaflet length (1.4 ± .27 cm vs. 1.25 ± .29, respectively; p < .01). Furthermore, the mitral annulus was more spherical, more flexible, and more dynamic in SAM+ patients than in SAM- patients (p < .05 for all). In a multivariate analysis of anatomic variables, the mitral-aortic angle, the mitral annular area, and posterior leaflet length were independent predictors of SAM (p ≤ .01 for all). In a multivariate analysis of standard echo and hemodynamic variables, the presence of wall motion abnormalities at rest (p < .01) was an independent predictor of SAM. CONCLUSION: SAM during DSE is multifactorial. In addition to the pharmacologic effects of dobutamine on the myocardium, 3D echocardiographic features of the mitral valve (a smaller mitral annulus, a narrower mitral-aortic angle, and a longer posterior leaflet) appear to predispose to SAM.

Prognostic value of transvalvular flow rate in patients with low-gradient severe aortic stenosis: A dobutamine stress echocardiography study.

BACKGROUNDS: There are limited data on the clinical relevance of transvalvular flow rate (Qmean ) at rest (Qrest) and at peak stress (Qstress ) during dobutamine stress echocardiography (DSE) in patients with low-gradient severe aortic stenosis (LG-SAS). METHODS: We retrospectively analyzed the clinical data of patients with LG-SAS who underwent DSE. LG-SAS was defined as an aortic valve (AV) area index of < .6 cm2 /m2 and a mean AV pressure gradient (AVPG) of < 40 mm Hg. The primary endpoint included all-cause death and heart failure hospitalization. RESULTS: Of 100 patients (mean age 79.5 ± 7.3 years; men, 45.0%; resting left ventricular ejection fraction [LVEF] 52.1% ± 15.9%; resting stroke volume index 35.8 ± 7.7 mL/m2 ; Qrest 171.8 ± 34.9 mL/s), the primary endpoint occurred in 51 patients during a median follow-up of 2.84 (interquartile range 1.01-5.21) years. When the study patients were divided into three subgroups based on Qrest and Qstress , the multivariate analysis showed that Qrest < 200 mL/s and Qstress ≥200 mL/s (hazard ratio 3.844; 95% confidence interval 1.143-12.930; p = .030), as well as Qrest and Qstress < 200 mL/s (hazard ratio 9.444; 95% confidence interval 2.420-36.850; p = .001), were significantly associated with unfavorable outcomes with Qrest and Qstress ≥200 mL/s as a reference after adjusting for resting LVEF, resting mean AVPG, chronic kidney disease, New York Heart Association functional class III/IV, and AV replacement. CONCLUSIONS: Flow conditions based on the combination of Qrest and Qstress are helpful for risk stratification in LG-SAS patients.

Should the Vasoactive Inotropic Score be a Determinant for Early Initiation of VA ECMO in Postcardiotomy Cardiogenic Shock?

OBJECTIVES: The authors investigated the role of early venoarterial extracorporeal membrane oxygenation (VA ECMO) implantation in patients with postcardiotomy cardiogenic shock (PCS) on mortality and morbidity when integrating vasoactive-inotropic score (VIS) and type of catecholamine support. DESIGN: A retrospective, multicenter, observational study with propensity-weight matching. SETTING: Four university-affiliated intensive care units. PARTICIPANTS: Patients with PCS in the operating room. INTERVENTIONS: Early VA ECMO support. MEASUREMENTS AND MAIN RESULTS: Of 2,742 patients screened during the study period, 424 (16%) patients were treated with inotropic drugs, and 75 (3%) patients were supported by VA ECMO in the operating room. Patients supported by VA ECMO had a higher use of vasopressor and inotropic drugs, with a higher VIS score. After propensity matching (integrating VIS and catecholamines type), mortality (56% v 20%, p < 0.001) and morbidity (cardiac, renal, transfusion) were higher in patients supported by VA ECMO than in a matched control group. CONCLUSIONS: When matching integrated the pre-ECMO VIS and the type of catecholamines, VA ECMO remained associated with high mortality and morbidity, suggesting that VIS alone should not be used as a main determinant of VA ECMO implantation.

Dobutamine Stress Cardiovascular Magnetic Resonance Derived 2-Dimension Feature Tracking Strain Analysis in Pediatric Population with Anomalous Aortic Origin of Right Coronary Artery.

Anomalous aortic origin of right coronary artery (AAORCA) is associated with myocardial ischemia and sudden cardiac arrest/death. Risk stratification remains challenging and relies upon provocative test results. This study describes the utility of dobutamine stress cardiovascular magnetic resonance (DSCMR) and potential benefit of strain analysis in children with AAORCA. All patients less than 21 years of age with AAORCA who underwent DSCMR between July 2018 and December 2022 were included. Visual wall motion abnormalities (VWMA) at rest and during protocolized increments of dobutamine infusion were assessed. Regional and global left ventricular circumferential (GCS) and radial (GRS) strain using 2-dimension Feature tracking (2D-FT) analysis (cvi42, Circle Cardiovascular Imaging Inc.) were calculated at rest and peak response. Of the total 54 DSCMR studies performed in 51 children with median age (IQR) of 13.5 (11-15) years, FT analysis was reliably performed in 52 (96%) studies. None had VWMA. The absolute change in GCS and GRS from rest to peak dobutamine stress was 4% (1-6%) and 11% (4-18%), respectively. There was no significant difference in GCS and GRS in patients with exertional symptoms vs no/non-exertional symptoms as well as between those considered to be high-risk vs low-risk anatomical features. DSCMR-derived 2D-FT strain analysis is feasible to assess myocardial deformation in children with AAORCA and may enhance this method of provocative testing. Although there were no statically significant differences in GCS and GRS values between high and low-risk subgroups, the absolute change in GCS between rest and peak stress is diminished when compared to normal adult reports.

Coronary Events Following Dobutamine Stress Cardiac Magnetic Resonance Imaging in Pediatric Patients.

Dobutamine stress cardiac magnetic resonance (dsCMR) has demonstrated value in identifying patients at risk for adverse cardiovascular events in adults with coronary artery disease, but its prognostic value in younger patients is unknown. This study sought to evaluate the relationship between dsCMR results and the risk of subsequent cardiovascular events in children. Patients age < 23 years who underwent dsCMR at Boston Children's Hospital were eligible for inclusion. Patients were excluded if no follow-up data were available after dsCMR or the dsCMR protocol was not completed. Data regarding the presence of inducible regional wall motion abnormalities and subsequent cardiovascular events during follow-up were analyzed. Cardiovascular events included myocardial infarction, surgical or catheter-based coronary artery intervention, and ischemic symptoms. Among 80 dsCMR studies in 64 patients with median age 5.3 years (range 0.5-22.4 years), 3 patients had a positive dsCMR with inducible regional wall motion abnormalities. Over a median follow-up of 7.4 years (IQR 4.0-11.2), 2 of these patients underwent surgical intervention (coronary artery bypass grafting and unroofing of a myocardial bridge) and the third remained asymptomatic with no interventions. Among 61 patients with a negative dsCMR, none experienced myocardial infarction, death, or aborted sudden death. Four underwent cardiac interventions (cardiac transplantation, coronary artery bypass grafting, and unroofing) due to symptoms or catheterization findings. In pediatric patients undergoing dsCMR, wall motion abnormalities indicating inducible ischemia were uncommon. Those with a negative dsCMR were unlikely to experience an adverse cardiac event or undergo a cardiac intervention on medium-term follow-up.

Quantitative evaluation of myocardial perfusion in coronary heart disease by myocardial contrast and dobutamine stress echocardiography.

OBJECTIVE: We aimed to investigate how combining myocardial contrast echocardiography (MCE) with dobutamine stress echocardiography (DSE) could help evaluate myocardial perfusion in coronary heart disease patients and understand changes in microcirculation across different levels of coronary artery blockage. METHODS: We conducted MCE and DSE tests on 53 coronary heart disease patients, categorizing ischemic myocardium into four groups: A (<50%), B (50%-69%), C (70%-89%), and D (≥90%). Dynamic myocardial perfusion images were captured during rest and peak dobutamine stress from various angles, analyzing parameters like plateau value A, slope ß, and the product A × ß, reflecting different aspects of myocardial blood flow. RESULTS: Parametric values of myocardial perfusion (PVMPs) were significantly lower in group D at rest compared with other groups (p < 0.001). PVMPs increased notably at peak dobutamine stress in groups A, B, and C (p < 0.001). Groups A and B had higher PVMPs than groups C and D, with group D significantly lower (p < 0.001). ß reserve values decreased gradually from group A to D, with significantly lower values of A and A × ß in groups C and D compared with A and B (p < 0.001). Sensitivity and specificity for predicting >70% coronary artery blockage was 80%, 66%, and 74%, 80%, respectively, using specific thresholds. CONCLUSION: Combining MCE with DSE is highly sensitive and accurate in diagnosing obstructive coronary artery blockages. It also helps assess myocardial microcirculation perfusion and left ventricular reserve function, which decline with increasing severity of coronary artery blockage.

The Effects of Dobutamine in Septic Shock: An Updated Narrative Review of Clinical and Experimental Studies.

The key objective in the hemodynamic treatment of septic shock is the optimization of tissue perfusion and oxygenation. This is usually achieved by the utilization of fluids, vasopressors, and inotropes. Dobutamine is the inotrope most commonly recommended and used for this purpose. Despite the fact that dobutamine was introduced almost half a century ago in the treatment of septic shock, and there is widespread use of the drug, several aspects of its pharmacodynamics remain poorly understood. In normal subjects, dobutamine increases contractility and lacks a direct effect on vascular tone. This results in augmented cardiac output and blood pressure, with reflex reduction in systemic vascular resistance. In septic shock, some experimental and clinical research suggest beneficial effects on systemic and regional perfusion. Nevertheless, other studies found heterogeneous and unpredictable effects with frequent side effects. In this narrative review, we discuss the pharmacodynamic characteristics of dobutamine and its physiologic actions in different settings, with special reference to septic shock. We discuss studies showing that dobutamine frequently induces tachycardia and vasodilation, without positive actions on contractility. Since untoward effects are often found and therapeutic benefits are occasional, its profile of efficacy and safety seems low. Therefore, we recommend that the use of dobutamine in septic shock should be cautious. Before a final decision about its prescription, efficacy, and tolerance should be evaluated throughout a short period with narrow monitoring of its wanted and side effects.

Multiaxial pressure-strain analysis of regional myocardial work in the setting of graded coronary stenoses and dobutamine stress.

We present a detailed analysis of regional myocardial blood flow and work to better understand the effects of coronary stenoses and low-dose dobutamine stress. Our analysis is based on a unique open-chest model in anesthetized canines that features invasive hemodynamic monitoring, microsphere-based blood flow analysis, and an extensive three-dimensional (3-D) sonomicrometer array that provides multiaxial deformational assessments in the ischemic, border, and remote vascular territories. We use this model to construct regional pressure-strain loops for each territory and quantify the loop subcomponent areas that reflect myocardial work contributing to the ejection of blood and wasted work that does not. We demonstrate that reductions in coronary blood flow markedly alter the shapes and temporal relationships of pressure-strain loops, as well as the magnitudes of their total and subcomponent areas. Specifically, we show that moderate stenoses in the mid-left anterior descending coronary artery decrease regional midventricle myocardial work indices and substantially increase indices of wasted work. In the midventricle, these effects are most pronounced along the radial and longitudinal axes, with more modest effects along the circumferential axis. We further demonstrate that low-dose dobutamine can help to restore or even improve function, but often at the cost of increased wasted work. This detailed, multiaxial analysis provides unique insight into the physiology and mechanics of the heart in the presence of ischemia and low-dose dobutamine, with potential implications in many areas, including the detection and characterization of ischemic heart disease and the use of inotropic support for low cardiac output.NEW & NOTEWORTHY Our unique experimental model assesses cardiac pressure-strain relationships along multiple axes in multiple regions. We demonstrate that moderate coronary stenoses decrease regional myocardial work and increase wasted work and that low-dose dobutamine can help to restore myocardial function, but often with further increases in wasted work. Our findings highlight the significant directional variation of cardiac mechanics and demonstrate potential advantages of pressure-strain analyses over traditional, purely deformational measures, especially in characterizing physiological changes related to dobutamine.

Dobutamine-induced alternations in cerebral blood flow of healthy adults: a 3D pseudocontinuous arterial spin labeling study.

BACKGROUND: It is unclear whether dobutamine, commonly used clinically in echocardiography and short-term congestive heart failure treatment for promoting increased myocardial contractility, affects brain microcirculatory behavior. Cerebral microcirculation plays an important role in ensuring adequate oxygen transport. Therefore, we investigated the effects of dobutamine on cerebral hemodynamics. METHODS: Forty-eight healthy volunteers without cardiovascular or cerebrovascular disease underwent MRI to obtain cerebral blood flow (CBF) maps using 3D pseudocontinuous arterial spin labeling before and during the dobutamine stress test. Additionally, cerebrovascular morphology was obtained based on 3D-time-off-light (3D-TOF) magnetic resonance angiography (MRA). Electrocardiogram, heart rate (HR), respiration rate (RR), blood pressure, and blood oxygen were simultaneously recorded before and during dobutamine injection and during recovery (not during MRI). The anatomic features of the circle of Willis and the basilar artery (BA) diameter were assessed on MRA images by two radiologists with extensive neuroimaging experience. Binary logistic regression was used to test for the independent determinants of CBF changes. RESULTS: HR, RR, systolic (SBP), and diastolic blood pressure (DBP) significantly increased after dobutamine infusion. Blood oxygen levels remained similar. Compared to the CBF in the resting state, the CBF values exhibited significantly lower CBF levels in both grey matter and white matter. Furthermore, compared with the CBF in the resting state, that in the stress state was decreased in the anterior circulation, mainly in the frontal lobe (voxel level P < 0.001, pixel level P < 0.05). Logistic regression showed that body mass index (BMI; odds ratio [OR] 5.80, 95% confidence interval [CI] 1.60-21.01, P = 0.008], resting SBP (OR 0.64, 95% CI 0.45-0.92, P = 0.014), and BA diameter (OR 11.04, 95% CI 1.05-116.53, P = 0.046) were significantly associated with frontal lobe CBF changes. CONCLUSIONS: Dobutamine-induced stress significantly decreased CBF in the frontal lobe anterior circulation. Individuals with a high BMI and low SBP during the dobutamine stress test are more likely to have a stress-induced CBF decrease. Thus, attention should be paid to blood pressure, BMI, and cerebrovascular morphology of patients undergoing dobutamine stress echocardiography or those receiving intensive care or anesthesia.

Major impact of vitamin D3 deficiency and supplementation on left ventricular torsional mechanics during dobutamine stress in uncomplicated type 2 diabetes.

BACKGROUND AND AIMS: Hypovitaminosis D is associated with the risk of diabetic complications. Its role in diabetic-related cardiac abnormalities remain poorly understood. We aimed therefore to evaluate the effect of vitamin D deficiency and supplementation on early left ventricular (LV) dysfunction in vitamin D deficient patients with uncomplicated T2D. METHODS AND RESULTS: Sixty-three consecutive T2D patients who had a diagnosis of vitamin D3 were prospectively recruited and allocated into 2 groups (25(OH)D < 20 ng/mL: VDD, >20 ng/mL VDND). Twenty-eight of them with 25(OH)D < 20 ng/mL benefited from a 3-month supplementation. At baseline and follow-up, after conventional echocardiography including evaluation of epicardial adipose tissue (EAT), both LV longitudinal (LS) and circumferential (CS) strains and rotation/twist mechanics were evaluated at rest and during dobutamine (DOB) stress. After treatment, T2D patients successfully normalized their 25(OH)D levels. The strongest associations between vitamin D deficiency and supplementation with LV myocardial function were noticed for torsional mechanics indexes under DOB. EAT correlated significantly (p < 0.01) with baseline 25(OH)D and was reduced after supplementation. Significant correlations were obtained between these 2 parameters with twist or apical rotation at baseline (p < 0.01) and between their delta changes at follow-up (p < 0.01) under DOB. Significant improvements in LS and CS (p < 0.05) under DOB were also underlined at follow-up, with major enhancements noticed in the apical region (p < 0.01) of the LV. CONCLUSIONS: This study provides the first evidences of the potential of vitamin D supplementation as an efficient prophylactic strategy to alleviate the progression of myocardial dysfunction in asymptomatic patients with uncomplicated T2D. CLINICALTRIALS: NCT03437421.

Dobutamine effects on systolic and diastolic left ventricular long-axis excursion and timing - significance for the interpretation of s' and e'.

BACKGROUND: Dobutamine effects on the relationships of the peak velocity of left ventricular (LV) long-axis systolic motion (s') with systolic excursion (SExc), systolic duration (SDur) and heart rate, of LV long-axis early diastolic excursion (EDExc) with SExc, and of the peak velocity of LV long-axis early diastolic motion (e') with EDExc, early diastolic duration (EDDur) and isovolumic relaxation time (IVRT') are unknown. METHODS: Two groups of adult subjects, one young and healthy (n = 10), and one with impaired LV long-axis function (n = 10), were studied, with the aim of identifying consistent findings for the two groups and for the septal and lateral walls. Dobutamine was infused at doses of 5 and 10 µg/kg/min. The relationships between tissue Doppler imaging (TDI) variables acquired before and during dobutamine infusion were analysed using mixed effect multivariate regression modelling. RESULTS: In both groups, heart rate increased and SDur decreased during dobutamine infusion, and there were independent inverse correlations of SDur with heart rate and dobutamine dose. In contrast, there was no change in EDDur during dobutamine infusion, and no consistent changes in IVRT' independent of heart rate. s' was positively correlated with SExc and inversely correlated with SDur, and there were positive correlations between EDExc and SExc and between e' and EDExc. CONCLUSION: Dobutamine increases s' due to effects on both systolic excursion and duration and it increases e' due to the associated increases in systolic and early diastolic excursion. A lack of effect on diastolic times does not support the presence of a lusitropic effect of dobutamine.

The evaluation of coronary microvascular obstruction in patients with STEMI by cardiac magnetic resonance T2-STIR image and layer-specific analysis of 2-dimensional speckle tracking echocardiography combined with low-dose dobutamine stress echocardiography.

This study was designed to assess coronary microvascular obstruction (MVO) in patients with acute ST-segment elevation myocardial infarction (STEMI) by cardiac magnetic resonance T2-weighted short tau inversion recovery (T2-STIR) image and layer-specific analysis of 2-dimensional speckle tracking echocardiography combined with low-dose dobutamine stress echocardiography (LDDSE-LS2D-STE). 32 patients were enrolled to perform cardiac magnetic resonance and echocardiography 5-7 days after primary percutaneous coronary intervention. Infarcted myocardium was categorized into MVO+ group and MVO- group by late gadolinium enhancement as gold standard. At T2-weighted image, the area of hyper-intense region and hypo-intense core inside were marked as A1, A2 and A2/A1 > 0 represented MVO. Strain parameters were composed of longitudinal strain (LS), circumferential strain and radial strain at rest and dobutamine stress. There were 94 MVO+ segments, 136 MVO- segments according to gold standard. 96 segments had hypo-intense core at T2-STIR image. The sensitivity and specificity of T2-STIR in detecting MVO were 91.49 and 92.65%. Endocardial LS was superior to other parameters, and stress endocardial LS was higher than that of resting endocardial LS (sensitivity: 77.11% vs 72.29%, specificity: 93.28% vs 83.19%, AUC: 0.87 vs 0.82, P < 0.05). The combination of T2-STIR and stress endocardial LS in parallel test could improve sensitivity significantly (98.05% vs 91.49%). T2-STIR has higher diagnostic value in detecting MVO with some limitations. However, LDDSE-LS2D-STE with cost-effective and handling may be a good alternative to T2-STIR. It provides additional and reliable diagnostic tools to identify MVO in STEMI patients after reperfusion.

Continuous Noninvasive Blood Pressure Measurement With "ClearSight" Compared to Standard Intermittent Blood Pressure Measurement in Patients With Peripheral Arterial Disease. Are Potential Differences Influenced by Phenylephrine or Dobutamine?

OBJECTIVES: To investigate the agreement between continuous noninvasive blood pressure measurement with the ClearSight system (cNIBP-CS) and standard intermittent noninvasive blood pressure measurement (iNIBP) in patients with peripheral arterial disease (PAD). Additionally, the influence of vasoactive medication on potential measurement differences was assessed. DESIGN: A secondary analysis of a randomized controlled trial. SETTING: At a university hospital. PARTICIPANTS: Thirty-four patients with PAD undergoing percutaneous transluminal angioplasty of the lower limbs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Continuous noninvasive blood pressures were measured with the "ClearSight" system and compared to standard iNIBPs. Bland-Altman analysis revealed a mean bias of 13 mmHg (±15) between cNIBP-CS and iNIBP, with 95% limits of agreement (LOA) ranging from -17 to 42 mmHg. When comparing both medication groups, a similar mean bias was found for phenylephrine and dobutamine (12 mmHg [±13] and 13 mmHg [±13], respectively). CONCLUSION: In this study, in patients with PAD, cNIBP-CS showed an underestimation of blood pressure compared to iNIBP in phenylephrine- and dobutamine-treated patients. Compared to previous studies, a larger bias and wider 95% LOA were found.

Prognostic value of extended cardiac risk assessment before elective open abdominal aortic surgery.

BACKGROUND: Major vascular surgery is associated with a high perioperative risk and significant mortality. Despite advances in risk stratification, monitoring, and management of perioperative complications, cardiac complications are still common. Stress echocardiography is well established in coronary artery disease diagnostics; however, its prognostic value before high-risk aortic surgery is unknown. This prospective, single-center study compared the outcome of patients undergoing extended cardiac risk assessment before open abdominal aortic surgery with the outcome of patients who had received standard preoperative assessment. METHODS: The study included patients undergoing elective open abdominal aortic surgery. Patients who underwent standard preoperative assessment before the start of a dedicated protocol were compared with patients who had extended cardiac risk assessment, including dobutamine stress echocardiography, as part of a stepwise interdisciplinary cardiovascular team approach. The combined primary endpoint was cardiovascular death, myocardial infarction, emergency coronary revascularization, and life-threatening arrhythmia within 30 days. The secondary endpoint was acute renal failure and severe bleeding. RESULTS: In total, 77 patients (mean age 68.1 ± 8.1 years, 70% male) were included: 39 underwent standard and 38 underwent cardiac risk assessment. The combined primary endpoint was reached significantly more often in patients before than after implementation of the extended cardiac stratification procedure (15% vs. 0%, p = 0.025). The combined secondary endpoint did not differ between the groups. CONCLUSIONS: Patients with extended cardiac risk assessment undergoing elective open abdominal aortic surgery had better 30-day outcomes than did those who had standard preoperative assessment.

Dobutamine-induced Takotsubo syndrome in a paediatric heart transplant patient.

Takotsubo syndrome is a potentially reversible cause of acute systolic dysfunction. Takotsubo syndrome is rare in children, with no reported dobutamine-induced cases to date. We present a 14-year-old male with prior history of heart transplantation, who developed Takotsubo syndrome during dobutamine stress echocardiography. We highlight the importance of its early recognition to ensure supportive measures with avoidance of inotropic medications.

Blood pressure control with phenylephrine or dobutamine: a randomized controlled trial comparing effects on cerebral and paravertebral tissue oxygen saturation measured with near-infrared spectroscopy.

Preserving haemodynamics is expected to positively affect tissue oxygen saturation. We hypothesized that maintaining mean arterial blood pressure (MAP) (using phenylephrine (PE) or dobutamine (Dobu)) would equally affect regional cerebral and paravertebral tissue saturation (rScO2 and rSpvO2, respectively). Thirty-four patients were randomly assigned to receive either PE or Dobu, in order to keep MAP within 20% of the preoperative value. Their effect on haemodynamics, rScO2 and rSpvO2 at thoracic level T3-T4, T9-T10 and lumbar level L1-L2 was calculated at different doses. Drug-induced haemodynamic effects differed between groups (∆MAP: -2%±21 and - 19%±17, ∆CI: -14.6%±14.6 and 24.1%±49.9, ∆HR: -21%±21 and 0%±16 for PE and Dobu, respectively). Both groups exhibited a significant decrease in rScO2, with a more pronounced decline in the PE group (-14.1%±16.1) compared to the Dobu group (-5.9%±10.6). There were no significant changes at the paravertebral level in either group, but a slight but statistically significant difference was detected between the two groups at T3-T4 and L1-L2. Current guidelines advocate maintaining adequate systemic blood pressures to prevent spinal cord ischaemia in specific procedures. However, it is still unknown which circulatory supportive drug is more beneficial for maintaining spinal cord perfusion. Our data indicates that, when used for maintenance of blood pressure within a 20% range of preoperative values, neither phenylephrine nor dobutamine affect paravertebral tissue saturation.

Acute myocardial infarction after a negative Dobutamine stress echocardiogram in a patient with end-stage liver disease.

Dobutamine stress echocardiogram (DSE) is generally a safe and reliable test for detection of myocardial ischaemia. We report the case of a 43-year-old male with end-stage liver disease (ESLD), who underwent DSE as part of workup for liver transplantation. Although the patient had an uneventful negative DSE, within 45 minutes he developed inferior ST-segment elevation myocardial infarction (STEMI). His coronary angiography showed severe 2-vessel coronary artery disease, which was treated with percutaneous coronary intervention (PCI) with implantation of drug-eluting stents (DES). Acute coronary syndrome (ACS) after a normal DSE has previously been reported in the literature. We describe one such case, with added complexity of managing an ACS in a patient with high bleeding risk. Our case is unique in reporting a STEMI after a negative DSE in a liver transplant recipient. Increased physician awareness of potential complications of DSE is essential to allow timely recognition and management.

Physical and physiological effects of dobutamine stress echocardiography in low-gradient aortic stenosis.

Dobutamine stress echocardiography (DSE) is a useful tool for assessing low-gradient significant aortic stenosis (AS) and contractile reserve (CR), but its prognostic utility has become controversial in recent studies. We evaluated the impact of DSE on aortic valve physiological, structural, and left ventricular parameters in low-gradient AS. Consecutive patients undergoing DSE for low-gradient AS evaluation from September 2010 to July 2016 were retrospectively studied, and DSE findings were divided into four groups: with and without severe AS and/or CR. Relationships between left ventricular chamber quantification, CR, aortic valve Doppler during DSE, and calcium score [by computerized tomography (CT)] were analyzed. There were 258 DSE studies performed on 243 patients, mean age 77.6 ± 10.8 yr and 183 (70.1%) were males. With increasing dobutamine dose, apart from systolic blood pressure, left ventricular ejection fraction, flow, cardiac power output, and longitudinal strain magnitude, along with aortic valve area and mean aortic gradient were all significantly increased (P < 0.05). Flow and mean gradient increased in both the presence and absence of CR, whereas stroke volume and aortic valve area increased mainly in those with CR only. The aortic valve area increased in both patients with low and high calcium scores; however, the baseline area was lower in those with a higher calcium score. During DSE, aortic valve area increases with increase in aortic valve gradient. Higher calcium score is associated with lower baseline aortic valve area, but the aortic valve area still increases with dobutamine even in presence of a high calcium score.NEW & NOTEWORTHY We show that even in most severe aortic stenosis, there is some residual valve pliability. This suggests that a complete loss of pliability is not compatible with survival.