Using Augmented Mean Arterial Pressure to Identify High Mortality Risk Patients With Moderate Aortic Stenosis

OBJECTIVE

To study the usefulness of a novel echocardiographic marker, augmented mean arterial pressure (AugMAP = [(mean aortic valve gradient + systolic blood pressure) + (2 × diastolic blood pressure)] / 3), in identifying high-risk patients with moderate aortic stenosis (AS).

PATIENTS AND METHODS

Adults with moderate AS (aortic valve area, 1.0-1.5 cm2) at Mayo Clinic sites from January 1, 2010, through December 31, 2020, were identified. Baseline demographic, echocardiographic, and all-cause mortality data were retrieved. Patients were grouped into higher and lower AugMAP groups using a cutoff value of 80 mm Hg for analysis. Kaplan-Meier and Cox regression models were used to assess the performance of AugMAP.

RESULTS

A total of 4563 patients with moderate AS were included (mean ± SD age, 73.7±12.5 years; 60.5% men). Median follow-up was 2.5 years; 36.0% of patients died. The mean ± SD left ventricular ejection fraction (LVEF) was 60.1%±11.4%, and the mean ± SD AugMAP was 99.1±13.1 mm Hg. Patients in the lower AugMAP group, with either preserved or reduced LVEF, had significantly worse survival performance (all P<.001). Multivariate Cox regression showed that AugMAP (hazard ratio, 0.962; 95% CI, 0.942 to 0.981 per 5-mm Hg increase; P<.001) and AugMAP less than 80 mm Hg (hazard ratio, 1.477; 95% CI, 1.241 to 1.756; P<.001) were independently associated with all-cause mortality.

CONCLUSION

AugMAP is a simple and effective echocardiographic marker to identify high-risk patients with moderate AS independent of LVEF. It can potentially be used in the candidate selection process if moderate AS becomes indicated for aortic valve intervention in the future.

Transcatheter Aortic Valve Replacement Prognostication with Augmented Mean Arterial Pressure

BACKGROUND

Post-transcatheter aortic valve replacement (TAVR) patient outcome is an important research topic. To accurately assess post-TAVR mortality, we examined a family of new echo parameters (augmented systolic blood pressure (AugSBP) and arterial mean pressure (AugMAP)) derived from blood pressure and aortic valve gradients.

METHODS

Patients in the Mayo Clinic National Cardiovascular Diseases Registry-TAVR database who underwent TAVR between 1 January 2012 and 30 June 2017 were identified to retrieve baseline clinical, echocardiographic and mortality data. AugSBP, AugMAP and valvulo-arterial impedance (Zva) (Zva) were evaluated using Cox regression. Receiver operating characteristic curve analysis and the c-index were used to assess the model performance against the Society of Thoracic Surgeons (STS) risk score.

RESULTS

The final cohort contained 974 patients with a mean age of 81.4 ± 8.3 years old, and 56.6% were male. The mean STS risk score was 8.2 ± 5.2. The median follow-up duration was 354 days, and the one-year all-cause mortality rate was 14.2%. Both univariate and multivariate Cox regression showed that AugSBP and AugMAP parameters were independent predictors for intermediate-term post-TAVR mortality (all p < 0.0001). AugMAP1 < 102.5 mmHg was associated with a 3-fold-increased risk of all-cause mortality 1-year post-TAVR (hazard ratio 3.0, 95%confidence interval 2.0-4.5, p < 0.0001). A univariate model of AugMAP1 surpassed the STS score model in predicting intermediate-term post-TAVR mortality (area under the curve: 0.700 vs. 0.587, p = 0.005; c-index: 0.681 vs. 0.585, p = 0.001).

CONCLUSIONS

Augmented mean arterial pressure provides clinicians with a simple but effective approach to quickly identify patients at risk and potentially improve post-TAVR prognosis.

Two cases of apical ballooning syndrome masking apical hypertrophic cardiomyopathy

Apical akinesis and dilation in the absence of obstructive coronary artery disease is a typical feature of stress-induced (takotsubo) cardiomyopathy, whereas apical hypertrophy is seen in apical-variant hypertrophic cardiomyopathy. We report the cases of 2 patients who presented with takotsubo cardiomyopathy and were subsequently found to have apical-variant hypertrophic cardiomyopathy, after the apical ballooning from the takotsubo cardiomyopathy had resolved. The first patient, a 43-year-old woman with a history of alcohol abuse, presented with shortness of breath, electrocardiographic and echocardiographic features consistent with takotsubo cardiomyopathy, and no significant coronary artery disease. An echocardiogram 2 weeks later revealed a normal left ventricular ejection fraction and newly apparent apical hypertrophy. The 2nd patient, a 70-year-old woman with pancreatitis, presented with chest pain, apical akinesis, and a left ventricular ejection fraction of 0.39, consistent with takotsubo cardiomyopathy. One month later, her left ventricular ejection fraction was normal; however, hypertrophy of the left ventricular apex was newly noted. To our knowledge, these are the first reported cases in which apical-variant hypertrophic cardiomyopathy was masked by apical ballooning from stress-induced cardiomyopathy.

Echocardiographic assessment of left ventricular diastolic function and filling pressure in atrial fibrillation

Diastolic dysfunction has been linked to 2 epidemics: atrial fibrillation (AF) and heart failure. The presence and severity of diastolic dysfunction are associated with an increased risk for first AF and first heart failure in patients with sinus rhythm. Furthermore, the risk for heart failure is markedly increased once AF develops. The evaluation of diastolic function once AF has developed remains a clinical challenge. The conventional use of Doppler echocardiography for the assessment and grading of diastolic dysfunction relies heavily on evaluating the relation of ventricular and atrial flow characteristics. The mechanical impairment of the left atrium and the variable cycle lengths in AF render the evaluation of diastolic function difficult. A few Doppler echocardiographic methods have been proved clinically useful for the estimation of diastolic left ventricular filling pressures in AF, but these appear to be underutilized. Several innovative methods are emerging that promise to provide greater precision in diastolic function assessment, but their clinical utility in AF remains to be established. In conclusion, this review provides an up-to-date discussion of the evaluation of diastolic function assessment in AF and how it may be important in the clinical management of patients with AF.

Preoperative dobutamine stress echocardiographic findings and subsequent short-term adverse cardiac events after orthotopic liver transplantation

Cardiovascular (CV) complications are the leading cause of non-graft-related death in orthotopic liver transplant (OLT) patients. Pretransplant cardiac evaluation using dobutamine stress echocardiography (DSE) is commonly utilized for risk stratification of OLT candidates. To determine if clinical and echocardiographic variables identify patients with increased CV risk, we performed a retrospective chart review of all 284 patients that underwent OLT at our institution between June 1999 and August 2005. Of these patients, 157 had a DSE prior to their OLT. Serious adverse CV events occurring during surgery and up to 4 months post-transplantation were defined as cardiac-related death, myocardial infarction (MI), new heart failure, or asystole or unstable ventricular arrhythmia requiring acute treatment. Sixteen of 157 patients (10%) had an adverse CV event with 2 deaths. These included ventricular tachycardia (n = 8), asystole (n = 2), MI (n = 5), and new heart failure (n = 1). Nine of the 16 CV events occurred at the time of surgery (including both deaths), 5 occurred postoperatively, and 3 occurred after hospital discharge. Variables that correlated with increased CV events were inability during DSE to achieve >82% of the maximum predicted heart rate (22% versus 6%, P = 0.01), a peak rate pressure product during DSE of <16,333 (17% versus 5%, P = 0.02), and a Model for End-Stage Liver Disease (MELD) score of >24 at the time of OLT. A multivariate model calculated from the DSE maximum achieved heart rate (MAHR) and MELD score (result = 3.78 + 0.07 MELD - 0.05 MAHR) identified a 47% risk for a value > 0 versus a 6% risk for a value < 0 (P < 0.001). In conclusion, the maximum heart rate achieved during DSE together with the MELD score may be a predictor of adverse CV events up to 4 months post-OLT. A large prospective study is needed to more decisively support this conclusion.

Relation of electrocardiographic criteria for left atrial enlargement to two-dimensional echocardiographic left atrial volume measurements

Left atrial (LA) enlargement by 2-dimensional (2-D) echocardiography predicts adverse cardiovascular outcomes. Electrocardiographic (ECG) criteria for LA enlargement are based on M-mode echocardiographic LA diameter, which is inferior to 2-D-derived LA volumes. This study compared established ECG criteria for LA enlargement with atrial volume obtained by 2-D echocardiography to determine if traditional ECG criteria accurately represent LA chamber enlargement, therefore offering a low-cost screening tool. A total of 261 randomly selected patients who underwent electrocardiography and 2-D echocardiography were enrolled. ECG parameters and electronically derived P-wave medians were analyzed with electronic calipers for maximal accuracy. LA volumes by 2-D echocardiography were measured with Simpson's method of discs, with enlargement defined as 32 ml/m(2). Sensitivity and specificity tables and receiver-operating characteristic curves were constructed for each criterion. Univariate and multivariate analyses were performed for predictors of 2-D echocardiographic LA enlargement. LA enlargement was present in 43% of patients. ECG P-wave duration was the most sensitive for the detection of LA enlargement (69%) but had low specificity (49%). Conversely, a biphasic P wave was the most specific (92%) but had low sensitivity (12%). The maximum area under the receiver-operating characteristic curve for any criterion was 0.64, too low to be of clinical utility. In conclusion, established ECG criteria for LA enlargement do not reliably reflect LA enlargement and lack sufficient predictive value to be useful clinically. These results suggest that P-wave abnormalities should be noted as nonspecific LA abnormalities, with the term "LA enlargement" no longer used.

Congenital absence of the pericardium: case presentation and review of literature

Congenital absence of the pericardium is an uncommon finding that may or may not be symptomatic. Asymptomatic patients are discovered incidentally during cardiac surgery for an unrelated condition or postmortem. However, symptomatic patients may experience non-exertional paroxysmal stabbing chest pain. It may occur with other cardiac or extracardiac abnormalities and a variety of imaging modalities may identify the condition. Complete cases are more rare than partial effects. However, complications are more common with partial absence due to strangulation of the heart into the defect thus requiring surgical intervention.

Effect of losartan and hydrochlorothiazide on exercise tolerance in exertional hypertension and left ventricular diastolic dysfunction

A randomized, double-blind study of 6 months of losartan 50 mg or hydrochlorothiazide (HCTZ) 12.5 mg was performed in 40 subjects with left ventricular diastolic dysfunction (mitral flow velocity E/A ratio < 1), exercise systolic blood pressure (BP) > 200 mm Hg, systolic BP at rest < 150 mm Hg, ejection fraction > 50%, and no ischemia. Before treatment, exercise systolic BP was 213 +/- 13 mm Hg (mean +/- SD) in the 19 patients randomized to losartan and 209 +/- 11 mm Hg in the 21 patients who received HCTZ. After 6 months, exercise systolic BP was similarly reduced in patients who received losartan (197 +/- 23 mm Hg, p < 0.01) and HCTZ (191 +/- 11 mm Hg, p < 0.01). With losartan, treadmill exercise time increased from 894 +/- 216 to 951 +/- 225 seconds (p = 0.011), and quality of life improved from 15 +/- 12 to 7 +/- 10 (p = 0.015) without a change in oxygen consumption (1,895 +/- 470 to 1,954 +/- 539 ml/min, p = 0.30). With HCTZ, exercise time (842 +/- 225 to 872 +/- 239 seconds, p = 0.32) and quality of life (19 +/- 21 vs 19 +/- 24, p = 0.43) did not change, whereas oxygen consumption decreased from 2,144 +/- 788 to 1,960 +/- 706 ml/min (p = 0.022). In conclusion, in patients with diastolic dysfunction and hypertensive responses to exercise, 6 months of losartan and HCTZ blunted systolic BP during exercise. Only losartan increased exercise tolerance and improved quality of life.

Cardiac syndrome X and endothelial dysfunction: new concepts in prognosis and treatment

Cardiac syndrome X (CSX), or angina with no flow-limiting stenosis on coronary angiogram, has been regarded as a condition with an excellent prognosis despite variable symptomatic improvement. Newer data show that patients with CSX with endothelial dysfunction have an increased risk for future adverse cardiac events. Current hypotheses of CSX pathophysiology emphasize a dysfunctional vascular endothelium that leads to microvascular ischemia. Treatments that target improving endothelial function, such as statins, angiotensin-converting enzyme inhibitors, estrogen, and lifestyle modification, are promising additions to treatment regimens for CSX. The goal of this article is to provide information for improved diagnosis, risk stratification, and therapy for the population with CSX.

Left Atrial Size

Left atrial (LA) enlargement has been proposed as a barometer of diastolic burden and a predictor of common cardiovascular outcomes such as atrial fibrillation, stroke, congestive heart failure, and cardiovascular death. It has been shown that advancing age alone does not independently contribute to LA enlargement, and the impact of gender on LA volume can largely be accounted for by the differences in body surface area between men and women. Therefore, enlargement of the left atrium reflects remodeling associated with pathophysiologic processes. In this review, we discuss the normal size and phasic function of the left atrium. Further, we outline the clinically important aspects and pitfalls of evaluating LA size, and the methods for assessing LA function using echocardiography. Finally, we review the determinants of LA size and remodeling, and we describe the evidence regarding the prognostic value of LA size. The use of LA volume for risk stratification is an evolving science. More data are required with respect to the natural history of LA remodeling in disease, the degree of LA modifiability with therapy, and whether regression of LA size translates into improved cardiovascular outcomes.

Doppler Tissue Imaging During Supine and Upright Exercise in Healthy Adults

Doppler tissue imaging variables were measured in 18 healthy men and women during supine bicycle stress exercise and upright exercise treadmill testing. From a color Doppler tissue imaging cineloop, tissue velocities in basal and mid segments of the standard 3 apical views during rest and peak exercise were assessed. Compared segments were adjusted for double product, and peak variables were compared using the paired t test. Peak systolic velocity and strain rate increased with both forms of exercise (P < .03). Time to compression-expansion crossover shortened in all segments with exercise and at peak exercise treadmill testing versus peak supine bicycle stress exercise (P < .03). Of all segments, 81% were analyzable for peak systolic velocity, 79% for strain rate. Doppler tissue imaging is a feasible tool for quantitatively assessing left ventricular response to supine and upright exercise.

The Doppler myocardial performance index during low-dose dobutamine echocardiography predicts mortality and left ventricular dilation after a first acute myocardial infarction

BACKGROUND

Myocardial viability can be detected by wall motion analysis during low-dose dobutamine echocardiography (LDDE) after acute myocardial infarction (AMI). However, wall motion analysis describes only left ventricular (LV) systolic reserve. The Doppler myocardial performance index (MPI) is a quantitative measure of combined LV systolic and diastolic function. We hypothesized that an increase (deterioration) in MPI during LDDE, reflecting reduced systolic and diastolic LV reserve, could provide prognostic information beyond conventional systolic wall motion analysis on mortality, morbidity, and LV remodeling after AMI.

METHODS

Low-dose dobutamine echocardiography (10 microg/kg per minute) was performed within 24 hours and echocardiography was repeated 5 days and 1, 3, and 6 months after a first AMI in 162 consecutive patients. Patients were followed for 25 +/- 11 months. End points were all-cause mortality and cardiac events (cardiac death or readmission for heart failure or reinfarction).

RESULTS

In 72 (44%) patients, MPI increased during LDDE. This was independently associated with subsequent LV dilation at 6 months of follow-up (beta = .73, P < .0001). An increase in MPI during LDDE was a powerful prognostic indicator and remained a predictor of mortality (HR 1.92, 95% CI 1.36-2.71, P < .0001) and cardiac events (HR 2.45, 95% CI 1.83-3.27, P < .0001) after adjustment for clinical data, indices of LV function at rest, and wall motion analysis during LDDE.

CONCLUSIONS

Early after AMI, deterioration in MPI during LDDE predicts subsequent LV dilation and provides prognostic information incremental to clinical data, indices of LV function at rest, and conventional stress echocardiographic data.

Echocardiographic predictors of morbidity and mortality in patients with advanced heart failure: the Beta-blocker Evaluation of Survival Trial (BEST)

OBJECTIVES

The aim of this study was to determine echocardiographic predictors of outcome in patients with advanced heart failure (HF) due to severe left ventricular (LV) systolic dysfunction in the Beta-blocker Evaluation of Survival Trial (BEST).

BACKGROUND

Previous studies indicate that echocardiographic measurements of LV size and function, mitral deceleration time, and mitral regurgitation (MR) predict adverse outcomes in HF. However, complete quantitative echocardiograms evaluating all of these parameters have not been reported in a prospective randomized clinical trial in the era of modern HF therapy.

METHODS

Complete echocardiograms were performed in 336 patients at 26 sites and analyzed by a core laboratory. A Cox proportional-hazards regression model was used to determine which echocardiographic variables predicted the primary end point of death or the secondary end point of death, HF hospitalization, or transplant. Significant variables were then entered into a multivariable model adjusted for clinical and demographic covariates.

RESULTS

On multivariable analysis adjusted for clinical covariates, only LV end-diastolic volume index predicted death (events = 75), with a cut point of 120 ml/m(2). Three echocardiographic variables predicted the combined end point of death (events = 75), HF hospitalization (events = 97), and transplant (events = 9): LV end-diastolic volume index, mitral deceleration time, and the vena contracta width of MR. Optimal cut points for these variables were 120 ml/m(2), 150 ms, and 0.4 cm, respectively.

CONCLUSIONS

Echocardiographic predictors of outcome in advanced HF include LV end-diastolic volume index, mitral deceleration time, and vena contracta width. These variables indicate that LV remodeling, increased LV stiffness, and MR are independent predictors of outcome in patients with advanced HF.

Ventricular tachycardia in the absence of structural heart disease

In up to 10% of patients who present with ventricular tachycardia (VT), obvious structural heart disease is not identified. In such patients, causes of ventricular arrhythmia include right ventricular outflow tract (RVOT) VT, extrasystoles, idiopathic left ventricular tachycardia (ILVT), idiopathic propranolol-sensitive VT (IPVT), catecholaminergic polymorphic VT (CPVT), Brugada syndrome, and long QT syndrome (LQTS). RVOT VT, ILVT, and IPVT are referred to as idiopathic VT and generally do not have a familial basis. RVOT VT and ILVT are monomorphic, whereas IPVT may be monomorphic or polymorphic. The idiopathic VTs are classified by the ventricle of origin, the response to pharmacologic agents, catecholamine dependence, and the specific morphologic features of the arrhythmia. CPVT, Brugada syndrome, and LQTS are inherited ion channelopathies. CPVT may present as bidirectional VT, polymorphic VT, or catecholaminergic ventricular fibrillation. Syncope and sudden death in Brugada syndrome are usually due to polymorphic VT. The characteristic arrhythmia of LQTS is torsades de pointes. Overall, patients with idiopathic VT have a better prognosis than do patients with ventricular arrhythmias and structural heart disease. Initial treatment approach is pharmacologic and radiofrequency ablation is curative in most patients. However, radiofrequency ablation is not useful in the management of inherited ion channelopathies. Prognosis for patients with VT secondary to ion channelopathies is variable. High-risk patients (recurrent syncope and sudden cardiac death survivors) with inherited ion channelopathies benefit from implantable cardioverter-defibrillator placement. This paper reviews the mechanism, clinical presentation, and management of VT in the absence of structural heart disease.

Echocardiographic determination of mean pulmonary artery pressure

We performed a simultaneous Doppler and invasive study to validate the role of Doppler-derived peak pulmonary regurgitant velocity as a reliable noninvasive measure of pulmonary artery mean pressure. Assessment of right atrial pressure, as shown in this study, enhances the use of this Doppler parameter as a correlate of pulmonary artery mean pressure.

Pneumopericardium and pneumothorax contralateral to venous access site after permanent pacemaker implantation

A 77-year-old female underwent implantation of a left-sided dual chamber permanent pacemaker for symptomatic bradycardia with active fixation leads. Eight hours after the procedure, the patient complained of shortness of breath and was found to have a 30% right pneumothorax on chest X-ray. Immediately, a chest tube was inserted, promptly relieving the symptoms. A CT scan of the chest revealed extrusion of the helix of the screw-in atrial lead, through the wall of the right atrial appendage. The helix was abutting a bulla in the right lung, the likely cause for pneumothorax and pneumopericardium. The atrial lead was explanted without incident.

A simple method for noninvasive estimation of pulmonary vascular resistance

OBJECTIVES

We sought to test whether the ratio of peak tricuspid regurgitant velocity (TRV, ms) to the right ventricular outflow tract time-velocity integral (TVI(RVOT), cm) obtained by Doppler echocardiography (TRV/TVI(RVOT)) provides a clinically reliable method to determine pulmonary vascular resistance (PVR).

BACKGROUND

Pulmonary vascular resistance is an important hemodynamic variable used in the management of patients with cardiovascular and pulmonary disease. Right-heart catheterization, with its associated disadvantages, is required to determine PVR. However, a reliable noninvasive method is unavailable.

METHODS

Simultaneous Doppler echocardiographic examination and right-heart catheterization were performed in 44 patients. The ratio of TRV/TVI(RVOT) was then correlated with invasive PVR measurements using regression analysis. An equation was modeled to calculate PVR in Wood units (WU) using echocardiography, and the results were compared with invasive PVR measurements using the Bland-Altman analysis. Using receiver-operating characteristics curve analysis, a cutoff value for the Doppler equation was generated to determine PVR >2WU.

RESULTS

As calculated by Doppler echocardiography, TRV/TVI(RVOT) correlated well (r = 0.929, 95% confidence interval 0.87 to 0.96) with invasive PVR measurements. The Bland-Altman analysis between PVR obtained invasively and that by echocardiography, using the equation: PVR = TRV/TVI(RVOT) x 10 + 0.16, showed satisfactory limits of agreement (mean 0 +/- 0.41). A TRV/TVI(RVOT) cutoff value of 0.175 had a sensitivity of 77% and a specificity of 81% to determine PVR >2WU.

CONCLUSIONS

Doppler echocardiography may provide a reliable, noninvasive method to determine PVR.

Left ventricular diastolic dysfunction as a predictor of the first diagnosed nonvalvular atrial fibrillation in 840 elderly men and women

OBJECTIVES

The objective of this study was to determine whether diastolic dysfunction is associated with increased risk of nonvalvular atrial fibrillation (NVAF) in older adults with no history of atrial arrhythmia.

BACKGROUND

Few data exist regarding the relationship between diastolic function and NVAF.

METHODS

The clinical and echocardiographic characteristics of patients age > or =65 years who had an echocardiogram performed between 1990 and 1998 were reviewed. Exclusion criteria were history of atrial arrhythmia, stroke, valvular or congenital heart disease, or pacemaker implantation. Patients were followed up in their medical records to the last clinical visit or death for documentation of first AF.

RESULTS

Of 840 patients (39% men; mean [+/- SD] age, 75 +/- 7 years), 80 (9.5%) developed NVAF over a mean (+/- SD) follow-up of 4.1 +/- 2.7 years. Abnormal relaxation, pseudonormal, and restrictive left ventricular diastolic filling were associated with hazard ratios of 3.33 (95% confidence interval [CI], 1.5 to 7.4; p = 0.003), 4.84 (95% CI, 2.05 to 11.4; p < 0.001), and 5.26 (95% CI, 2.3 to 12.03; p < 0.001), respectively, when compared with normal diastolic function. After a number of adjustments, diastolic function profile remained incremental to history of congestive heart failure and previous myocardial infarction for prediction of NVAF. Age-adjusted Kaplan-Meier five-year risks of NVAF were 1%, 12%, 14%, and 21% for normal, abnormal relaxation, pseudonormal, and restrictive diastolic filling, respectively. CONCLUSIONS; The presence and severity of diastolic dysfunction are independently predictive of first documented NVAF in the elderly.

Generalized tetany: an unusual complication during dobutamine stress echocardiography

Dobutamine stress echocardiography is a frequently used noninvasive method for the evaluation of inducible myocardial ischemia, myocardial viability, and preoperative cardiac risk. Although its clinical safety has been validated, side effects and complications especially with the coadministration of atropine can occur. We report a case of generalized tetany in a 49-year-old woman undergoing dobutamine stress echocardiography.

Pulmonary venous pressure: relationship to pulmonary artery, pulmonary wedge, and left atrial pressure in normal, lightly sedated dogs

Because pulmonary venous pressure has never been measured, it is unclear whether pulmonary wedge pressure measures left atrial pressure, as commonly assumed, or pressure more upstream in the pulmonary venous or capillary beds. Fluid-filled mean pulmonary artery and pulmonary wedge pressure were compared with pulmonary venous and left atrial pressure obtained with high-fidelity micromanometer catheters in eight lightly sedated dogs over a physiologic range of filling pressures. In all conditions, mean pulmonary wedge pressure was virtually identical (r = 0.99) to mean left atrial pressure (slope = 0.99; intercept = -0.46 mm Hg). At the same time, mean pulmonary venous pressure (17.1 +/- 6.5 mm Hg) was intermediate between mean pulmonary artery pressure (20.2 +/- 6.2 mm Hg) and mean pulmonary wedge pressure (13.3 +/- 6.2 mm Hg; P < 0.0001) or mean left atrial pressure (13.4 +/- 6.3 mm Hg; P < 0.0001). These relationships were maintained over normal and increased pressure ranges. As measured by conventional flow-directed pulmonary catheters, mean pulmonary wedge pressure accurately reflects left atrial pressure in lightly sedated, spontaneously breathing normal dogs.

Color M-mode and pulsed wave tissue Doppler echocardiography: powerful predictors of cardiac events after first myocardial infarction

To assess the association between color M-mode flow propagation velocity and the early diastolic mitral annular velocity (E(m)) obtained with tissue Doppler echocardiography and to assess the prognostic implications of the indexes, echocardiography was performed on days 1 and 5, and 1 and 3 months after a first myocardial infarction in 67 consecutive patients. Flow propagation velocity correlated well with E(m) (r = 0.72, P <.0001). The ratio of peak E-wave velocity (E) to flow propagation velocity also correlated well with E/E(m) (r = 0.87, P <.0001). The positive predictive value of E/FPV > or =1.5 to identify patients with Killip class > or =II was 90%, and the negative predictive value 92%. The corresponding values for E/E(m) > or =10 were 70% and 90%. Cox proportional hazards analysis identified E/flow propagation velocity > or =1.5 (relative risk, 12.4 [95% confidence interval, 4.1-37.3]), E/E(m) > or =10 (relative risk, 11.5 [95% confidence interval, 3.8-34.7]), and Killip class > or =II (relative risk, 7.8 [95% confidence interval, 1.6-40.4]) to be predictors of the composite end point of cardiac death and readmission because of heart failure. Thus flow propagation velocity and E(m) are closely related after myocardial infarction and appear to have similar prognostic information.

Serial Doppler echocardiographic assessment of left and right ventricular performance after a first myocardial infarction

We sought to investigate the relation between left ventricular (LV) and right ventricular (RV) function assessed with the Doppler-derived myocardial performance index (MPI), to assess serial changes, and to investigate the prognostic value of biventricular assessment of cardiac function after a first myocardial infarction (MI). To do so, serial Doppler echocardiography was performed in 77 consecutive patients with a first MI. Right ventricular MPI correlated significantly with LV MPI (r = 0.51, P <.0001). In patients with echocardiographic signs of RV MI, the RV MPI was significantly higher (0.59 +/- 0.18 versus 0.44 +/- 0.19, P =.001), whereas no difference in LV MPI was seen (0.55 +/- 0.19 versus 0.56 +/- 0.13, P = not significant). Right ventricular MPI showed a rapid normalization during follow-up, whereas LV MPI did not decrease. During follow-up, 23 patients died of cardiac causes or were readmitted because of worsening heart failure. Multivariate Cox analysis indicated LV MPI (relative risk 4.9 [95% CI 1.8-13.5], P =.002) and RV MPI (relative risk 3.8 [1.3-17.0], P =.01) to be predictors of cardiac events. Thus the RV MPI is frequently abnormal after a first MI but normalizes rapidly on follow-up, and biventricular assessment of cardiac function may improve the prognostic accuracy compared with LV assessment alone.

Clinical utility of Doppler echocardiography and tissue Doppler imaging in the estimation of left ventricular filling pressures: A comparative simultaneous Doppler-catheterization study

BACKGROUND

Noninvasive assessment of diastolic filling by Doppler echocardiography provides important information about left ventricular (LV) status in selected subsets of patients. This study was designed to assess whether mitral annular velocities as assessed by tissue Doppler imaging are associated with invasive measures of diastolic LV performance and whether additional information is gained over traditional Doppler variables.

METHODS AND RESULTS

One hundred consecutive patients referred for cardiac catheterization underwent simultaneous Doppler interrogation. Invasive measurements of LV pressures were obtained with micromanometer-tipped catheters, and the mean LV diastolic pressure (M-LVDP) was used as a surrogate for mean left atrial pressure. Doppler signals from the mitral inflow, pulmonary venous inflow, and TDI of the mitral annulus were obtained. Isolated parameters of transmitral flow correlated with M-LVDP only when ejection fraction <50%. The ratio of mitral velocity to early diastolic velocity of the mitral annulus (E/E') showed a better correlation with M-LVDP than did other Doppler variables for all levels of systolic function. E/E' <8 accurately predicted normal M-LVDP, and E/E' >15 identified increased M-LVDP. Wide variability was present in those with E/E' of 8 to 15. A subset of those patients with E/E' 8 to 15 could be further defined by use of other Doppler data.

CONCLUSIONS

The combination of tissue Doppler imaging of the mitral annulus and mitral inflow velocity curves provides better estimates of LV filling pressures than other methods (pulmonary vein, preload reduction). However, accurate prediction of filling pressures for an individual patient requires a stepwise approach incorporating all available data.

The echo-Doppler evaluation of left ventricular diastolic function. A current perspective

The role of left ventricular (LV) diastolic function in health and disease is still incompletely understood and under appreciated by most primary care physicians and many cardiologists. Physical examination, electrocardiogram, and chest radiographs are unreliable in making the diagnosis of LV diastolic dysfunction in most individuals, and invasive measurements of cardiac pressures, rates of LV relaxation, and LV compliance are costly, clinically impracticable as they carry increased risk, and require special catheters and software analysis programs. The authors address the definition of LV diastolic dysfunction, history of diastole, LV filling patterns, pulmonary venous flow velocity variables, additional ancillary data, practical echo-Doppler evaluation of LV diastolic function, and limitations.

Ratio of left ventricular peak E-wave velocity to flow propagation velocity assessed by color M-mode Doppler echocardiography in first myocardial infarction: prognostic and clinical implications

OBJECTIVES

To determine the ability of the ratio of peak E-wave velocity to flow propagation velocity (E/Vp) measured with color M-mode Doppler echocardiography to predict in-hospital heart failure and cardiac mortality in an unselected consecutive population with first myocardial infarction (MI).

BACKGROUND

Several experimental studies indicate color M-mode echocardiography to be a valuable tool in the evaluation of diastolic function, but data regarding the clinical value are lacking.

METHODS

Echocardiography was performed within 24 h of arrival at the coronary care unit in 110 consecutive patients with first MI. Highest Killip class was determined during hospitalization. Patients were divided into groups according to E/Vp <1.5 and > or =1.5.

RESULTS

During hospitalization 53 patients were in Killip class > or =II. In patients with E/Vp > or =1.5, Killip class was significantly higher compared with patients with E/Vp <1.5 (p < 0.0001). Multivariate logistic regression analysis identified E/Vp > or =1.5 to be the single best predictor of in-hospital clinical heart failure when compared with age, heart rate, E-wave deceleration time (Dt), left ventricular (LV) ejection fraction, wall motion index, enzymatic infarct size and Q-wave MI. At day 35 survival in patients with E/Vp <1.5 was 98%, while for patients with E/Vp > or =1.5, it was 58% (p < 0.0001). Cox proportional hazards model identified Dt <140 ms, E/Vp > or =1.5 and age to be independent predictors of cardiac death, with Dt < 140 ms being superior to age and E/Vp.

CONCLUSIONS

In the acute phase of MI, E/Vp > or =1.5 measured with color M-mode echocardiography is a strong predictor of in-hospital heart failure. Furthermore, E/Vp is superior to systolic measurements in predicting 35 day survival although Dt <140 ms is the most powerful predictor of cardiac death.

Comparison of mitral inflow and superior vena cava Doppler velocities in chronic obstructive pulmonary disease and constrictive pericarditis

OBJECTIVE

This study was conducted to determine whether Doppler recording of superior vena cava flow velocities can differentiate chronic obstructive pulmonary disease from constrictive pericarditis in patients with a respiratory variation of > or = 25% in mitral inflow E velocity.

BACKGROUND

Although respiratory variation (> or = 25%) in mitral E velocity is the main diagnostic criterion for constrictive pericarditis by Doppler echocardiography, it can also be present in chronic obstructive pulmonary disease. Because the respiratory variation is due to increased change in intrathoracic pressure with respiration in chronic obstructive pulmonary disease, and to dissociation of intrathoracic-intracardiac pressure changes in constriction, it was hypothesized that the Doppler flow velocity pattern in the superior vena cava (affected by intrathoracic pressure) would be different in these two conditions.

METHODS

Pulsed-wave Doppler recording of mitral and superior vena cava flow velocities in 20 patients with chronic obstructive pulmonary disease who had > or = 25% respiratory variation in mitral E-wave velocity were compared with those of 20 patients who had surgically proved constrictive pericarditis.

RESULTS

Constrictive pericarditis and chronic obstructive pulmonary disease had similar respiratory variation in mitral E velocity (41% versus 46%). In the latter, the E/A ratio was lower (inspiration, 0.8+/-0.3 versus 1.5+/-0.7 [p < 0.0001]; expiration, 1.0+/-0.3 vs. 1.9+/-0.7 [p < 0.0001]) and deceleration time longer (inspiration, 198+/-53 ms versus 137+/-32 ms; expiration, 225+/-43 ms vs. 161+/-33 ms [p < 0.0001]). Inspiratory superior vena cava systolic forward flow velocity was significantly higher in chronic obstructive pulmonary disease (72.9+/-22.6 cm/s versus 36.2+/-9.3 cm/s, p < 0.0001), while expiratory systolic forward flow velocity was similar. Hence, there was a significantly greater respiratory variation in superior vena cava systolic forward flow velocity in chronic obstructive pulmonary disease without an overlap with constrictive pericarditis (39.5+/-18.8 cm/s vs. 4.2+/-3.4 cm/s, p < 0.0001).

CONCLUSIONS

Despite a similar respiratory variation in mitral E wave velocities, mitral inflow variables in chronic obstructive pulmonary disease are less restrictive compared with those in constrictive pericarditis. More importantly, patients with chronic obstructive pulmonary disease show a marked increase in inspiratory superior vena cava systolic forward flow velocity, which is not seen in patients with constrictive pericarditis.

Age independence of the difference in duration of pulmonary venous atrial reversal flow and transmitral A-wave flow in normal subjects

Aging influences pulmonary venous flow and mitral inflow velocities. The duration of pulmonary venous atrial reversal flow exceeds that of the mitral inflow A wave in patients with left ventricular end-diastolic pressures greater than 15 mm Hg. The objective of this study was to investigate the effect of age on the difference between the duration of pulmonary venous atrial reversal flow and that of the mitral inflow A wave in a large number of normal individuals. Pulsed wave Doppler transthoracic echocardiograms of the pulmonary venous flow and the transmitral inflow with respiratory monitoring were made of 72 normal volunteers (40 women) ranging in age between 23 and 84 years. The differences in the durations of pulmonary venous atrial reversal flow and mitral inflow A wave were measured and their correlation with age assessed. Age was not highly correlated with the duration of pulmonary venous atrial reversal flow (r = 0.25) nor the duration of the mitral inflow A wave (r = 0.33). The duration of pulmonary venous atrial reversal flow exceeded the duration of the mitral inflow A-wave flow only in three (4%) of 72 subjects, and age was not related to the index in this group (r = -0.16; p = 0.19). The difference in durations was not significantly affected by the phase of respiration. Men had higher values on all measurements than women. The difference between the pulmonary venous atrial reversal duration and the mitral inflow A-wave duration is independent of age and thus may be used as a reliable index of left ventricular end-diastolic pressure, even in elderly patients.

Determination of left ventricular filling pressure by Doppler echocardiography in patients with coronary artery disease: critical role of left ventricular systolic function

OBJECTIVES

This study was designed to determine the usefulness of transthoracic Doppler measurements in detecting increased left ventricular (LV) end-diastolic pressure in patients with coronary artery disease, specifically examining the influence of systolic function on the accuracy of these methods.

BACKGROUND

Studies that have correlated Doppler indexes with LV filling pressures primarily involved patients with LV systolic dysfunction. The reliability of Doppler indexes in estimating filling pressures in patients with coronary artery disease and preserved systolic function is unclear.

METHODS

Pulsed wave Doppler transmitral and pulmonary venous flow velocity curves and LV pressure were recorded in 83 patients with coronary artery disease.

RESULTS

Conventional Doppler indexes (deceleration time of mitral E wave velocity, ratio of peak mitral E to A wave velocities and pulmonary venous systolic fraction) correlated with LV filling pressure in patients with an ejection fraction (EF) < or = 50% but not in those with an EF > 50%. Previously published regression analysis for prediction of LV filling pressure was accurate in patients with an EF < or = 50% but not in those with an EF > 50%. The difference between flow duration with atrial contraction in the pulmonary veins and transmitral flow duration with atrial contraction correlated with LV filling pressure in both groups.

CONCLUSIONS

Analysis of the early diastolic portion of the transmitral or pulmonary venous flow velocity curves can be used to predict LV filling pressures in patients with systolic dysfunction, but are inaccurate in patients with preserved systolic function. The combined analysis of both flow velocity curves at atrial contraction is a reliable, feasible predictor of increased LV filling pressure, irrespective of systolic function.

Hemodynamic determinants of Doppler pulmonary venous flow velocity components: new insights from studies in lightly sedated normal dogs

OBJECTIVES

We sought to define the hemodynamic determinants of pulmonary venous (PV) flow velocities to assess how these are affected by respiration, heart rate and loading conditions.

BACKGROUND

Pulmonary venous flow velocity (PVFV) recorded with pulsed wave Doppler technique is currently used in the noninvasive evaluation of left ventricular (LV) diastolic function and filling pressures. Although previous studies in both animals and humans have shown that PV flow is pulsatile, the hemodynamic determinants of the individual components of this flow remain controversial. Understanding the physiologic mechanisms should help to better define the clinical utility of these Doppler techniques.

METHODS

PV flow velocities obtained with transesophageal pulsed wave Doppler imaging were recorded together with PV, left atrial (LA) and LV pressures in 10 sedated, spontaneously breathing normal dogs. PVFV and hemodynamic data were analyzed during apnea, inspiration and expiration, at atrial paced heart rates of 60, 80, 100 and 120 beats/min and mean LA pressures of 6, 12, 18 and 24 mm Hg.

RESULTS

The data showed that 1) PV pressure varied depending on recording site, resembling pulmonary artery pressure closer to the pulmonary capillary bed and LA pressure closer to the venoatrial junction; 2) PVFV qualitatively followed changes in the PV-LA pressure gradient; 3) four PVFV components exist under normal conditions-three of which follow phasic changes in LA pressure and one of which (the late systolic component) is more influenced by RV stroke volume and the compliance of the pulmonary veins and left atrium; 4) normal respiration and changes in heart rate significantly alter PVFV variables--in particular, reverse flow velocity at atrial contraction; and 5) increasing LA pressure results in larger PV A wave and PV early systolic flow velocities, as well as an earlier peak in PV late systolic flow velocity and a more prominent velocity minimum before PV diastolic flow.

CONCLUSIONS

Using transesophageal pulsed wave Doppler technique, four PVFV components are identifiable and determined by PV-LA hemodynamic pressure gradients. These gradients appear to be influenced by a combination of physiologic events that include RV stroke volume, the compliance of the pulmonary vasculature and left atrium and phasic changes in LA pressure. PV flow velocity components are significantly influenced by heart rate, respiration and LA pressure. These findings have implications for the interpretation of LV diastolic function and filling pressures by current Doppler echocardiographic techniques but require further clinical investigation.

Utility of preload alteration in assessment of left ventricular filling pressure by Doppler echocardiography: a simultaneous catheterization and Doppler echocardiographic study

OBJECTIVES

The aim of this study was to demonstrate the usefulness of preload alterations in assessing left ventricular filling pressures with transmitral Doppler velocity curves.

BACKGROUND

Doppler mitral inflow velocities, used to estimate left ventricular filling pressures noninvasively, are limited in predicting left ventricular filling pressures, especially in patients with normal systolic function and a "pseudonormal" mitral filling pattern.

METHODS

Forty-nine patients were studied in the cardiac catheterization laboratory with simultaneous Doppler echocardiography using high fidelity catheters to compare left ventricular diastolic filling pressures (pre-A wave left ventricular pressure) and Doppler mitral inflow at baseline and during reduction of preload during the strain phase of the Valsalva maneuver (n = 27) or sublingual nitroglycerin (n = 36), or both (n = 14). Doppler measurements consisted of E (initial peak velocity), A (velocity at atrial contraction), deceleration time (time from E velocity to deceleration of flow extrapolated to baseline) and absolute A wave velocity (A' [peak A wave velocity minus velocity at onset of atrial contraction]).

RESULTS

In patients with high pre-A wave pressure (> or 15 mm Hg), there was a greater change in the E/A' ratio during the Valsalva maneuver than in patients with a normal pre-A wave pressure (-1.22 +/- 1.1 vs. -0.35 +/- 0.17; p = 0.02). A similar change was seen when comparing the change in the E/A' ratio after administration of nitroglycerin in patients with a high versus a normal pre-A wave pressure (0.81 +/- 0.49 vs. 0.18 +/- 0.17; p < 0.001). These differences were present in patients with a normal E/A ratio at baseline.

CONCLUSIONS

Alterations in preload during assessment of Doppler echocardiographic indexes may be useful in noninvasively assessing left ventricular filling pressures.

Doppler evaluation of left and right ventricular diastolic function: a technical guide for obtaining optimal flow velocity recordings

Doppler mitral flow velocities and related variables are used to assess left (LV) and right ventricular filling and, indirectly, ventricular diastolic function. Three abnormal ventricular filling patterns (impaired relaxation and pseudonormal and restrictive physiology) are recognized in patients with various heart diseases and have been related to alterations in LV diastolic properties and filling pressures. More recently, these variables have been used to assess the hemodynamic effects of drug therapy or heart surgery and prognosis in patients with restrictive and dilated cardiomyopathies. Despite these encouraging results, widespread clinical use of these Doppler techniques has been hampered by difficulties in obtaining accurate and reproducible measurements from Doppler flow velocity recordings. This is due, in part, to an underappreciation of factors such as cardiac filling mechanics, Doppler examination principles, and ultrasound machine settings, which can markedly affect the quality of the flow velocity recordings. The purpose of this article is to provide the technical information for performing a systematic and comprehensive Doppler evaluation of LV diastolic function that can be used on a routine basis. This information includes discussing the different flow velocity recordings required for a Doppler assessment of LV diastolic function, their proper recording technique, and the common technical pitfalls.

The noninvasive assessment of left ventricular diastolic function with two-dimensional and Doppler echocardiography

Left ventricular diastolic filling can be determined reliably by Doppler-derived mitral and pulmonary venous flow velocities. Diastolic filling abnormalities are broadly classified at their extremes to impaired relaxation and restrictive physiology with many patterns in between. An impaired relaxation pattern identifies patients with early stages of heart disease, and appropriate therapy may avert progression and functional disability. Pseudonormalization is a transitional phase between abnormal relaxation and restrictive physiology and signifies increased filling pressure and decreased compliance. In this phase, reducing preload, optimizing afterload, and treating the underlying disease are clinically helpful. A restrictive physiology pattern identifies advanced, usually symptomatic disease with a poor prognosis. Therapeutic intervention is directed toward normalizing loading conditions and improving the restrictive filling pattern, although this may not be feasible in certain heart diseases. Finally, many patients have left ventricular filling patterns that appear indeterminate or mixed. In these cases, clinical information, left atrial and left ventricular size, pulmonary venous flow velocity, and alteration of preload help assess diastolic function and estimate diastolic filling pressures.

Preload reduction to unmask the characteristic Doppler features of constrictive pericarditis. A new observation

BACKGROUND

Respiratory variation of > or = 25% in mitral E velocity is a characteristic Doppler echocardiographic feature in constrictive pericarditis. However, a subset of patients with constriction do not exhibit the typical respiratory change, most likely because of marked increase in the left atrial pressure, and preload reduction may unmask the respiratory variation.

METHODS AND RESULTS

In 12 patients with surgically confirmed constrictive pericarditis who had < 25% respiratory variation in mitral E velocity during an initial preoperative examination, the Doppler study was repeated after an attempt to decrease left ventricular filling pressure. At baseline, mean mitral E velocity was similar after inspiration and expiration (0.81 +/- 0.24 and 0.84 +/- 0.21 m/s, respectively). On repeat Doppler examination, with the patient in a head-up tilt or sitting position the decrease in mitral E velocity with inspiration (0.61 +/- 0.13 m/s) was significant (P < .004), whereas it did not change significantly with expiration. The mean percent respiratory change in E velocity was 5 +/- 7% at baseline and 32 +/- 28% with preload reduction. Eight (75%) of the 12 patients developed respiratory variation of > or = 25%.

CONCLUSIONS

When the respiratory variation in Doppler mitral E velocity is blunted or absent during the evaluation of suspected constrictive pericarditis, repeat Doppler recording of mitral flow velocities after maneuvers to decrease preload is recommended to unmask the characteristic respiratory variation in mitral E velocity.