A multicentric quality-control study of exercise Doppler echocardiography of the right heart and the pulmonary circulation. The RIGHT Heart International NETwork (RIGHT-NET).

PURPOSE: This study was a quality-control study of resting and exercise Doppler echocardiography (EDE) variables measured by 19 echocardiography laboratories with proven experience participating in the RIGHT Heart International NETwork. METHODS: All participating investigators reported the requested variables from ten randomly selected exercise stress tests. Intraclass correlation coefficients (ICC) were calculated to evaluate the inter-observer agreement with the core laboratory. Inter-observer variability of resting and peak exercise tricuspid regurgitation velocity (TRV), right ventricular outflow tract acceleration time (RVOT Act), tricuspid annular plane systolic excursion (TAPSE), tissue Doppler tricuspid lateral annular systolic velocity (S'), right ventricular fractional area change (RV FAC), left ventricular outflow tract velocity time integral (LVOT VTI), mitral inflow pulsed wave Doppler velocity (E), diastolic mitral annular velocity by TDI (e') and left ventricular ejection fraction (LVEF) were measured. RESULTS: The accuracy of 19 investigators for all variables ranged from 99.7 to 100%. ICC was > 0.90 for all observers. Inter-observer variability for resting and exercise variables was for TRV = 3.8 to 2.4%, E = 5.7 to 8.3%, e' = 6 to 6.5%, RVOT Act = 9.7 to 12, LVOT VTI = 7.4 to 9.6%, S' = 2.9 to 2.9% and TAPSE = 5.3 to 8%. Moderate inter-observer variability was found for resting and peak exercise RV FAC (15 to 16%). LVEF revealed lower resting and peak exercise variability of 7.6 and 9%. CONCLUSIONS: When performed in expert centers EDE is a reproducible tool for the assessment of the right heart and the pulmonary circulation.

The Right Heart International Network (RIGHT-NET): Rationale, Objectives, Methodology, and Clinical Implications.

The Right Heart International Network is a multicenter international study aiming to prospectively collect exercise Doppler echocardiography tests of the right heart pulmonary circulation unit (RHPCU) in large cohorts of healthy subjects, elite athletes, and individuals at risk of or with overt pulmonary hypertension. It is going to provide standardization of exercise stress echocardiography of RHPCU and explore the full physiopathologic response.

Exercise Stress Echocardiography of the Right Ventricle and Pulmonary Circulation.

BACKGROUND: Exercise echocardiography is used for assessment of pulmonary circulation and right ventricular function, but limits of normal and disease-specific changes remain insufficiently established. OBJECTIVES: The objective of this study was to explore the physiological vs pathologic response of the right ventricle and pulmonary circulation to exercise. METHODS: A total of 2,228 subjects were enrolled: 375 healthy controls, 40 athletes, 516 patients with cardiovascular risk factors, 17 with pulmonary arterial hypertension, 872 with connective tissue diseases without overt pulmonary hypertension, 113 with left-sided heart disease, 30 with lung disease, and 265 with chronic exposure to high altitude. All subjects underwent resting and exercise echocardiography on a semirecumbent cycle ergometer. All-cause mortality was recorded at follow-up. RESULTS: The 5th and 95th percentile of the mean pulmonary artery pressure-cardiac output relationships were 0.2 to 3.5 mm Hg.min/L in healthy subjects without cardiovascular risk factors, and were increased in all patient categories and in high altitude residents. The 5th and 95th percentile of the tricuspid annular plane systolic excursion to systolic pulmonary artery pressure ratio at rest were 0.7 to 2.0 mm/mm Hg at rest and 0.5 to 1.5 mm/mm Hg at peak exercise, and were decreased at rest and exercise in all disease categories and in high-altitude residents. An increased all-cause mortality was predicted by a resting tricuspid annular plane systolic excursion to systolic pulmonary artery pressure <0.7 mm/mm Hg and mean pulmonary artery pressure-cardiac output >5 mm Hg.min/L. CONCLUSIONS: Exercise echocardiography of the pulmonary circulation and the right ventricle discloses prognostically relevant differences between healthy subjects, athletes, high-altitude residents, and patients with various cardio-respiratory conditions. (Right Heart International NETwork During Exercise in Different Clinical Conditions; NCT03041337).

Pilot study of cardiac magnetic resonance imaging for detection of embolic source after ischemic stroke.

BACKGROUND: Transesophageal echocardiography (TEE) is the standard for evaluating cardioembolic sources of stroke, although many strokes remain cryptogenic after TEE. Cardiac magnetic resonance (CMR) imaging may have advantages over TEE. We performed a prospective pilot study comparing CMR to TEE after stroke to assist in planning future definitive studies. METHODS: Individuals with nonlacunar stroke within 90 days of undergoing clinical TEE were prospectively identified and underwent a 1.5 Tesla research CMR scan. Exclusion criteria included >50% relevant cervical vessel stenosis and inability to undergo nonsedated CMR. A descriptive comparison of cardioembolic source (intracardiac thrombus/mass, aortic atheroma ≥ 4 mm, or patent foramen ovale [PFO]) by study type was performed. RESULTS: Twenty patients underwent CMR and TEE a median of 6 days apart. The median age was 51 years (interquartile range [IQR] 40, 63.5), 40% had hypertension, 15% had diabetes, 25% had a previous stroke/transient ischemic attack, 5% had atrial fibrillation, and none had coronary disease or heart failure. No patient had intracardiac thrombus or mass detected on either study. Aortic atheroma ≥ 4 mm thick was identified by TEE in 1 patient. CMR identified aortic atheroma as <4 mm in this patient (3 mm on CMR compared with 5 mm on TEE). PFO was identified in 6 of 20 patients on TEE; CMR found only 1 of these. CONCLUSIONS: In this pilot study, TEE identified more potential cardioembolic sources than CMR imaging. Future studies comparing TEE and CMR after stroke should focus on older subjects at higher risk for cardiac disease to determine whether TEE, CMR, or both can best elucidate potential cardioembolic sources.

Feasibility of semi-recumbent bicycle exercise Doppler echocardiography for the evaluation of the right heart and pulmonary circulation unit in different clinical conditions: the RIGHT heart international NETwork (RIGHT-NET).

Exercise Doppler echocardiography (EDE) is a well-validated tool in ischemic and valvular heart diseases. However, its use in the assessment of the right heart and pulmonary circulation unit (RH-PCU) is limited. The aim of this study is to assess the semi-recumbent bicycle EDE feasibility for the evaluation of RH-PCU in a large multi-center population, from healthy individuals and elite athletes to patients with overt or at risk of developing pulmonary hypertension (PH). From January 2019 to July 2019, 954 subjects [mean age 54.2 ± 16.4 years, range 16-96, 430 women] underwent standardized semi-recumbent bicycle EDE with an incremental workload of 25 watts every 2 min, were prospectively enrolled among 7 centers participating to the RIGHT Heart International NETwork (RIGHT-NET). EDE parameters of right heart structure, function and pressures were obtained according to current recommendations. Right ventricular (RV) function at peak exercise was feasible in 903/940 (96%) by tricuspid annular plane systolic excursion (TAPSE), 667/751 (89%) by tissue Doppler-derived tricuspid lateral annular systolic velocity (S') and 445/672 (66.2%) by right ventricular fractional area change (RVFAC). RV-right atrial pressure gradient [RV-RA gradient = 4 × tricuspid regurgitation velocity2 (TRV)] was feasible in 894/954 patients (93.7%) at rest and in 816/954 (85.5%) at peak exercise. The feasibility rate in estimating pulmonary artery pressure improved to more than 95%, if both TRV and/or right ventricular outflow tract acceleration time (RVOT AcT) were considered. In high specialized echocardiography laboratories semi-recumbent bicycle EDE is a feasible tool for the assessment of the RH-PCU pressure and function.

Metoprolol reverses left ventricular remodeling in patients with asymptomatic systolic dysfunction: the REversal of VEntricular Remodeling with Toprol-XL (REVERT) trial.

BACKGROUND: There are no randomized, controlled trial data to support the benefit of beta-blockers in patients with asymptomatic left ventricular systolic dysfunction. We investigated whether beta-blocker therapy ameliorates left ventricular remodeling in asymptomatic patients with left ventricular systolic dysfunction. METHOD AND RESULTS: Patients with left ventricular ejection fraction <40%, mild left ventricular dilation, and no symptoms of heart failure (New York Heart Association class I) were randomly assigned to receive extended-release metoprolol succinate (Toprol-XL, AstraZeneca) 200 mg or 50 mg or placebo for 12 months. Echocardiographic assessments of left ventricular end-systolic volume, end-diastolic volume, mass, and ejection fraction were performed at baseline and at 6 and 12 months. The 149 patients randomized to the 3 treatment groups (200 mg, n=48; 50 mg, n=48; and placebo, n=53) were similar with regard to all baseline characteristics including age (mean, 66 years), gender (74% male), plasma brain natriuretic peptide (79 pg/mL), left ventricular end-diastolic volume index (110 mL/m2), and left ventricular ejection fraction (27%). At 12 months in the 200-mg group, there was a 14+/-3 mL/m2 decrease (least square mean+/-SE) in end-systolic volume index and a 6+/-1% increase in left ventricular ejection fraction (P<0.05 versus baseline and placebo for both). The decrease in end-diastolic volume index (14+/-3) was different from that seen at baseline (P<0.05) but not with placebo. In the 50-mg group, end-systolic and end-diastolic volume indexes decreased relative to baseline but were not different from what was seen with placebo, whereas ejection fraction increased by 4+/-1% (P<0.05 versus baseline and placebo). CONCLUSION: Beta-blocker therapy can ameliorate left ventricular remodeling in asymptomatic patients with left ventricular systolic dysfunction.

Stressing the Cardiopulmonary Vascular System: The Role of Echocardiography.

The cardiopulmonary vascular system represents a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is considered the gold standard for assessing pulmonary hemodynamics, a comprehensive noninvasive evaluation including left and right ventricular reserve and function and cardiopulmonary interactions remains highly attractive. Stress echocardiography is crucial in the evaluation of many cardiac conditions, typically coronary artery disease but also heart failure and valvular heart disease. In stress echocardiographic applications beyond coronary artery disease, the assessment of the cardiopulmonary vascular system is a cornerstone. The possibility of coupling the left and right ventricles with the pulmonary circuit during stress can provide significant insight into cardiopulmonary physiology in healthy and diseased subjects, can support the diagnosis of the etiology of pulmonary hypertension and other conditions, and can offer valuable prognostic information. In this state-of-the-art document, the topic of stress echocardiography applied to the cardiopulmonary vascular system is thoroughly addressed, from pathophysiology to different stress modalities and echocardiographic parameters, from clinical applications to limitations and future directions.

Prognostic role of transesophageal echocardiography in acute type A aortic dissection.

BACKGROUND: Acute type A aortic dissection (AAD) remains a highly lethal entity for which emergent surgical correction is standard care. Prior studies have identified specific clinical findings as being predictive of outcome. The prognostic significance of specific findings on imaging studies is less well described. We sought to identify the prognostic value of transesophageal echocardiography (TEE) in medically and surgically treated patients with AAD. METHODS: We studied 522 AAD patients enrolled over 6 years in the International Registry of Acute Aortic Dissection who underwent TEE. Multivariate analysis identified independent associations of inhospital mortality, first using clinical variables (model 1), after which TEE data were added to build a final model (model 2). RESULTS: Inhospital mortality was 28.7%. Transesophageal echocardiographic evidences of pericardial effusion (P = .04), tamponade (P < .01), periaortic hematoma (P = .02), and patent false lumen (P = .08) were more frequent in nonsurvivors. Dilated ascending aorta (P = .03), dissection localized to the ascending aorta (P = .02), and thrombosed false lumen (P = .08) were less common in nonsurvivors. Model 1 identified age > or = 70 years, any pulse deficit, renal failure, and hypotension/shock as independent predictors of death. Model 2 identified dissection flap confined to ascending aorta (odds ratio 0.2, 95% CI 0.1-0.6) and complete thrombosis of false lumen (odds ratio 0.15, 95% CI 0.03-0.86) as protective. In the medically treated group, mortality was 31% for subjects with a partially or completely thrombosed false lumen versus 66% in the presence of a patent false lumen. CONCLUSIONS: Transesophageal echocardiography provides prognostic information in AAD beyond that provided by clinical risk variables.

Evans blue staining of cardiomyocytes induced by myocardial contrast echocardiography in rats: evidence for necrosis instead of apoptosis.

High mechanical index (MI) echocardiography with contrast agent has been shown to induce Evans blue staining of cardiomyocytes, seen 1 d after exposure, in addition to contraction band necrosis, seen immediately after exposure. This research examined the roles of necrosis vs. apoptosis in these bioeffects. Myocardial contrast echocardiography at high MI with 1:4 electrocardiogram triggering was performed in anesthetized rats at 1.5 MHz. Histologically observable cell injury was accumulated by infusing a high dose of 50 microL/kg ultrasound contrast media via tail vein for 5 min at the start of 10 min of scanning. Evans blue dye or propidium iodide was injected as an indicator of cardiomyocyte plasma membrane integrity. Histologic sections were stained using the terminal dUTP nick-end labeling (TUNEL) method for labeling nuclei with DNA degradation (e.g., apoptosis). Evans blue fluorescent cells were counted on frozen sections or on hematoxylin-stained and TUNEL-labeled paraffin sections. In addition, transmission electron microscopy was used to assess potential apoptotic nuclei. Hypercontraction and propidium iodide staining were observed immediately after imaging exposure. Although TUNEL-positive cells were evident after 4 h, these also had indications of contraction band necrosis, and features of apoptosis were not confirmed by electron microscopy. Inflammatory cell infiltration was evident after 24 h. A second, more subtle injury was recognized by Evans blue staining, with minimal inflammatory cell infiltration at the morphologically intact stained cells after 24 h. Apoptosis was not detected by the TUNEL method in the cardiomyocytes stained with Evans blue at 24 h. However, Evans blue-stained cell numbers declined after 48 h, with continued inflammatory cell infiltration. The initial insult for Evans blue-stained cardiomyocytes apparently induced partial permeability of the plasma membrane, which led to gradual degeneration (but not apoptosis) and necrosis after 24 to 48 h.

Impact of ejection fraction on infectious, renal, and respiratory morbidity for patients undergoing noncardiac surgery.

OBJECTIVE: We sought to determine if decreased left ventricular systolic function was associated with an increased risk of postoperative infectious, respiratory, or renal complications in patients undergoing noncardiac surgery. DESIGN: Retrospective cohort study. SETTING: Single tertiary-care, university-based medical center. PATIENTS: We studied individuals who participated in the American College of Surgeons National Quality Improvement Program and had a preoperative echocardiogram conducted at our institution. INTERVENTIONS: None. MEASUREMENTS: The incidences of postoperative respiratory (need for postoperative mechanical ventilation or unplanned intubation), renal (acute renal failure or renal insufficiency), and infectious (pneumonia, urinary tract infection, sepsis, or wound infection) complications were analyzed. MAIN RESULTS: Postoperative infections (n=175, 10%) represented the most common postoperative complication seen in the study population of 1692 individuals. Respiratory complications occurred in 77 (5%) and renal complications occurred in 29 (2%) participants. The time between the echocardiogram and surgery ranged from 7 months (interquartile range [IQR] 1.8-15.7) for those with severely reduced left ventricular ejection fraction (LVEF) to 24 months (IQR 2.5-38.6) for those with a normal LVEF (P=.038). Univariate analysis demonstrated a relationship between decreased preoperative LVEF and infectious and renal complications, but not respiratory complications. After adjusting for preoperative characteristics, decreased preoperative LVEF was associated with infectious (odds ratio, 1.33; 95% confidence interval, 1.03-1.68; P=.0265) and renal (odds ratio, 1.69; 95% confidence interval, 1.12-2.48; P=.0142) complications. CONCLUSIONS: Decreased preoperative LVEF is associated with postoperative infections and renal complications.

Stress echocardiography: current methodology and clinical applications.

Stress echocardiography is commonly employed for the clinical management of known or suspected coronary artery disease. This review discusses the accuracy of the technique, which is equivalent to that of competing imaging techniques, as well as its overall role in patient management. The utilization of stress echocardiographic modalities in clinical presentations, such as chest pain, congestive heart failure, and valvular heart disease, and preoperative risk assessment, as well as determining myocardial viability, are discussed.

Predicting death in patients with acute type a aortic dissection.

BACKGROUND: Given the high mortality rates in patients with type A aortic dissection, predictive tools to identify patients at increased risk of death are needed to assist clinicians for optimal treatment. METHODS AND RESULTS: Accordingly, we evaluated 547 patients with this diagnosis enrolled in the International Registry of Acute Aortic Dissection (IRAD) between January 1996 and December 1999. Univariate testing followed by multivariate logistic regression analysis was performed to identify independent predictors of death. In-hospital mortality rate was 32.5% in type A dissection patients. In-hospital complications (neurological deficits, altered mental status, myocardial or mesenteric ischemia, kidney failure, hypotension, cardiac tamponade, and limb ischemia) were increased in patients who died compared with survivors (P<0.05 for all). Logistic regression identified the following presenting variables as predictors of death: age > or =70 years (OR, 1.70; 95% CI, 1.05 to 2.77; P=0.03), abrupt onset of chest pain (OR 2.60; 95% CI, 1.22 to 5.54; P=0.01), hypotension/shock/tamponade (OR, 2.97; 95% CI, 1.83 to 4.81; P<0.0001), kidney failure (OR, 4.77; 95% CI, 1.80 to 12.6; P=0.002), pulse deficit (OR, 2.03; 95% CI, 1.25 to 3.29, P=0.004), and abnormal ECG (OR, 1.77; 95% CI, 1.06 to 2.95; P=0.03) (area under receiver operating curve, 0.74; Hosmer-Lemeshow statistic, P=0.75). CONCLUSIONS: The in-hospital mortality rate in acute type A aortic dissection is high and can be predicted with the use of a clinical model incorporated in a simple risk prediction tool. This tool can be used to educate patients with dissection about their predicted risk and in clinical research for risk adjustment while comparing outcomes of different therapies.

Consensus conference report: maximizing use of organs recovered from the cadaver donor: cardiac recommendations, March 28-29, 2001, Crystal City, Va.

The shortage of available donor hearts continues to limit cardiac transplantation. For this reason, strict criteria have limited the number of patients placed on the US waiting list to approximately 6000 to 8000 per year. Because the number of available donor hearts has not increased beyond approximately 2500 per year, the transplant waiting list mortality rate remains substantial. Suboptimal and variable utilization of donor hearts has compounded the problem in the United States. In 1999, the average donor yield from 55 US regions was 39%, ranging from 19% to 62%. This report provides the detailed cardiac recommendations from the conference on "Maximizing Use of Organs Recovered From the Cadaver Donor" held March 28 to 29, 2001, in Crystal City, Va. The specific objective of the report is to provide recommendations to improve the evaluation and successful utilization of potential cardiac donors. The report describes the accuracy of current techniques such as echocardiography in the assessment of donor heart function before recovery and the impact of these data on donor yield. The rationale for and specific details of a donor-management pathway that uses pulmonary artery catheterization and hormonal resuscitation are provided. Administrative recommendations such as enhanced communication strategies among transplant centers and organ-procurement organizations, financial incentives for organ recovery, and expansion of donor database fields for research are also described.

Acute type A aortic dissection in the elderly: clinical characteristics, management, and outcomes in the current era.

OBJECTIVES: We sought to evaluate the clinical characteristics, management, and outcomes of elderly patients with acute type A aortic dissection. BACKGROUND: Few data exist on the clinical manifestations and outcomes of acute type A aortic dissection in an elderly patient cohort. METHODS: We categorized 550 patients with type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection into two age strata (<70 and >or=70 years) and compared their clinical features, management, and in-hospital events. RESULTS: Thirty-two percent of patients with type A dissection were aged >or=70 years. Marfan syndrome was exclusively associated with dissection in the young, whereas hypertension, atherosclerosis and iatrogenic dissection predominated in older patients. Typical symptoms (abrupt onset of chest or back pain) and signs (aortic regurgitation murmur or pulse deficits) of dissection were less common among the elderly. Fewer elderly patients were managed surgically than younger patients (64% vs. 86%, p < 0.0001). Hypotension occurred more frequently (46% vs. 32%, p = 0.002) and focal neurologic deficits less frequently (18% vs. 26%, p = 0.04) among the elderly. In-hospital mortality was higher among older patients (43% vs. 28%, p = 0.0006). Logistic regression analysis identified age >or=70 years as an independent predictor of hospital death for acute type A aortic dissection (odds ratio 1.7, 95% confidence interval 1.1-2.8; p = 0.03). CONCLUSIONS: Our study shows significant differences between older (age >or=70 years) and younger (age <70 years) patients with acute type A aortic dissection in their clinical characteristics, management, and hospital outcomes. Future research should evaluate strategies to improve outcomes in this high-risk elderly cohort.

The influence of agent delivery mode on cardiomyocyte injury induced by myocardial contrast echocardiography in rats.

Myocardial contrast echocardiography (MCE) can induce bioeffects in rat hearts by local activation of the contrast agent gas bodies. This study was designed to examine the influence of agent delivery mode on the magnitude of cardiomyocyte injury. A total of 69 hairless rats were anesthetized and mounted vertically in a water bath. Evans blue dye was injected as vital stain for cardiomyocyte injury. Definity contrast agent was diluted in saline and injected via tail vein at 20 or 80 microL/kg in bolus or infusion mode. In 12 rats, 0.57 mg/kg dipyridamole was given to simulate a stress test. MCE in a short axis view with 1:4 or 1:16 ECG triggering was performed at 1.5 MHz for 5 or 20 min. The peak rarefactional pressure amplitude was set to 1.1 or 2.0 MPa. Premature beats were counted from the ECG record. Evans blue fluorescent cells were counted on frozen sections from the center of the scan plane of heart samples obtained 24 h postMCE. Infusion of the contrast agent led to more cardiomyocyte injury than did bolus injection. Dipyridamole stress also increased the effect. Varying the infusion rate or trigger interval was less important than the overall dosage during scanning. Exposure at 1.1 MPa and 80 microL/kg yielded significant cell killing relative to shams. Premature beats generally followed the same trends as cell injury, except that lower infusion rates tended to increase this effect. Contrast agent delivery mode, as well as dose and peak rarefactional pressure amplitude, has a significant influence on the bioeffects potential of MCE.

Prognostic significance of mitral regurgitation and tricuspid regurgitation in patients with left ventricular systolic dysfunction.

BACKGROUND: Mitral regurgitation (MR) and tricuspid regurgitation (TR) frequently develop in patients with left ventricular systolic dysfunction (LVSD). Ventricular volume overload that occurs in patients with MR and TR may lead to progression of myocardial dysfunction. We hypothesized that MR and TR would provide markers of risk in patients with LVSD. METHODS: We reviewed clinical, electrocardiographic, and echocardiographic data on 1421 consecutive patients with LVSD (left ventricular ejection fraction < or =35%). Predictors of survival (freedom from death or United Network for Organ Sharing [UNOS]-1 transplantation) were identified in a multivariable analysis with a Cox proportional hazards analysis. The impact of MR and TR (none to mild, moderate, or severe) then was assessed separately with Kaplan-Meier survival analysis. RESULTS: During the follow-up period (mean +/- SD, 365 +/-364 days), death occurred in 435 study subjects (31%) and UNOS-1 transplantation in 28 subjects (2%). Multivariable predictors of poor outcome included increasing MR and TR grade, cancer, coronary artery disease, and absence of an implantable cardiac defibrillator. Relative risk was 1.84 (95% CI 1.43-2.38) for severe MR and 1.55 (95% CI 1.14-2.11) for severe TR. Survival with Kaplan-Meier analysis related inversely to MR grade (none to mild 1004 +/-31 days, moderate 795 +/-34 days, severe 628 +/-47 days, P <.0001) and TR grade (none to mild 977 +/-28 days, moderate 737 +/-40 days, severe 658 +/-55 days, P =.0001). CONCLUSION: Patients with severe MR or TR represent high-risk subsets of patients with LVSD. Future study is warranted to determine whether pharmaceutical or surgical strategies to relieve MR and TR have a favorable impact on survival.

Range and prevalence of cardiac abnormalities in patients hospitalized in a medical ICU.

BACKGROUND: Patients hospitalized in medical ICUs (MICUs) with acute noncardiac illnesses have an undefined prevalence of underlying cardiovascular abnormalities. Because of the acuteness of illness, the need for frequent concurrent mechanical ventilation, and the nature of the underlying diseases, routine cardiac examination may be suboptimal for identifying concurrent cardiac abnormalities. PURPOSE: The purpose of this study was to utilize transthoracic echocardiography and Doppler echocardiography interrogation to identify the range and prevalence of occult cardiac abnormalities that may be present in patients admitted to an MICU. METHODS: Over a 12-month period, 500 consecutive patients who had been admitted to the MICU of a large university tertiary care center underwent complete two-dimensional echocardiography and Doppler scanning within 18 h of admission. The final study population comprised 467 patients. No study subject had been admitted to the MICU for a primary cardiac diagnosis. Cardiovascular abnormalities were prospectively defined, and all echocardiograms were interpreted independently by blinded observers. Both MICU and overall mortality rates as well as length of stay were compared to the presence or absence of cardiac abnormalities. RESULTS: One or more cardiac abnormalities was noted in 169 patients (36%). The average (+/-SD) age of patients in the study was 52 +/- 17 years (age range, 17 to 100 years), and the average age was 57 +/- 18 years (age range, 18 to 93 years) in patients with underlying cardiac abnormalities. A single cardiac abnormality was noted in 103 patients (22%), two cardiac abnormalities were noted in 34 patients (7.2%), and three or more cardiac abnormalities were noted in 32 patients (6.8%). Based on subsequent requests for cardiac diagnostic studies, 67 patients (14.3%) were clinically suspected of having significant cardiovascular abnormalities, 39 of whom (58%) had one or more cardiac abnormalities on seen on echocardiography. Cardiac abnormalities were unsuspected in 130 of 169 patients (77%) and were only noted at the time they underwent surveillance echocardiography. Although there was no correlation between the presence of cardiac abnormalities and mortality, both MICU and hospital length of stay were increased in patients with cardiac abnormalities. CONCLUSION: A significant proportion of patients admitted to an MICU with noncardiac illness have underlying cardiac abnormalities, which can be detected with surveillance echocardiography at the time of admission. Cardiac abnormalities were associated with an increased length of stay but not with increased mortality.

Feasibility of transesophageal echocardiography with a ten-French monoplane probe.

OBJECTIVES: We examined the feasibility of transesophageal echocardiography (TEE) using a 10F monoplane probe developed for intracardiac ultrasound (AcuNav, Acuson/Siemens, Mountain View, Calif). BACKGROUND: Traditional TEE uses a 10- to 12-mm-diameter probe, and conscious sedation is customary to minimize patient discomfort. Because of its small size (3.2-mm diameter), the 10F monoplane probe can be inserted into the esophagus using only topical anesthesia. This provides the potential for a more easily tolerated examination. METHODS: A total of 20 patients underwent a comprehensive TEE using an adult multiplane probe. Immediately afterward, the 10F monoplane probe was inserted into the esophagus and a targeted examination completed. The 10F monoplane studies were blindly reviewed by 3 observers for the study indication and for 16 diagnostic elements. These were graded against an expert's review of standard TEE. RESULTS: The 10F monoplane probe was well tolerated in all patients. Observers A, B, and C answered the clinical question in 80%, 85%, and 100%, respectively, with the 10F probe. The percentage of clinical elements deemed evaluable was 71%, 78%, and 80%, respectively. Limitations included incomplete visualization of the mitral valve and a systematic underestimation of the severity of valve regurgitation. CONCLUSIONS: The 10F monoplane probe is safe, well-tolerated, and capable of evaluating many clinical questions. Because of its small size, conscious sedation may not be necessary. It may be useful for targeted evaluations, for monitoring invasive procedures, or for intermediate or long-term monitoring in an intensive care department.

Impact of myocardial contrast echocardiography on vascular permeability: comparison of three different contrast agents.

Microvascular permeabilization, petechial hemorrhage and premature ventricular contractions (PVCs) have been demonstrated in an in vivo rat model of myocardial contrast echocardiography (MCE). The purpose of this study was to compare these effects for three US Food and Drug Administration (FDA)-approved ultrasound (US) contrast agents (US CA): Optison, Definity and Imagent. Evans blue dye, an indicator of microvascular permeability, and a contrast agent were injected IV in anesthetized rats suspended in a water bath to mimic scanning depths seen in clinical echocardiology. Diagnostic US B-mode scans with 1:4 end-systolic triggering were performed at 1.7 MHz using a cardiac phased-array scanhead to provide a short axis view of the left ventricle. To elicit readily measurable effects for comparisons, relatively high doses of the agent were used (50 to 500 microL kg(-1) for Optison, 25 to 200 microL kg(-1) for Imagent, 10 to 100 microL kg(-1) for Definity). Microvascular leakage was characterized by the area of Evans blue dye coloration on the hearts and by extraction of the dye from tissue samples. The number of petechia were counted on the epicardial surface of excised hearts. PVCs were counted from ECG traces recorded with the MCE images. Neither evidence of capillary leakage nor PVCs were seen in sham animals. Based on volume dose, Definity MCE produced more microvascular leakage, but there was no apparent difference between the three agents' microvascular damage potential, which increased linearly with dose at low doses, when expressed in terms of the number of stabilized microbubbles. Definity MCE resulted in fewer PVCs than the other agents. The effects increased strongly with peak rarefactional pressure amplitude, with apparent thresholds for petechiae at 0.4 MPa and for PVCs at about 1.0 MPa. These results should be of value for minimizing adverse potential in diagnosis and optimizing efficacy in therapeutic applications.