Echocardiographic left ventricular diastolic dysfunction predicts hospital mortality after out-of-hospital cardiac arrest

PURPOSE

To determine whether systolic or diastolic dysfunction on transthoracic echocardiogram (TTE) predicts mortality after out-of-hospital cardiac arrest (OHCA).

METHODS

Retrospective cohort study of 173 OHCA subjects undergoing targeted temperature management who underwent TTE during hospitalization. Univariate analysis and multivariate logistic regression were used to determine associations between TTE measurements of systolic and diastolic function and systemic hemodynamics with all-cause mortality.

RESULTS

Mean age was 61.6 ± 12.4 years (72.7% male) and initial rhythm was shockable in 89%. Hospital mortality was 30.6%. Mean LVEF was 40% and was not different in hospital survivors (p = 0.81). TTE parameters reflecting systolic function and systemic hemodynamics did not predict hospital mortality. Medial mitral E/e' ratio was associated with hospital mortality, with an optimal cut-off > 13 (p = 0.002). After multivariate adjustment, medial mitral E/e' ratio remained predictive of hospital mortality (OR 1.11, 95% CI 1.03-1.20, p = 0.004). Subjects with a medial mitral E/e' ratio > 13 had higher mortality during long-term follow-up (p < 0.001 by log-rank).

CONCLUSIONS

Diastolic dysfunction (higher medial mitral E/e' ratio) on TTE independently predicted mortality after OHCA; systolic dysfunction and TTE hemodynamic parameters did not. This reflects a novel use of Doppler TTE to predict outcomes after OHCA.

Basic and advanced echocardiographic evaluation of myocardial dysfunction in sepsis and septic shock

Sepsis continues to be a leading cause of mortality and morbidity in the intensive care unit. Cardiovascular dysfunction in sepsis is associated with worse short- and long-term outcomes. Sepsis-related myocardial dysfunction is noted in 20%-65% of these patients and manifests as isolated or combined left or right ventricular systolic or diastolic dysfunction. Echocardiography is the most commonly used modality for the diagnosis of sepsis-related myocardial dysfunction. With the increasing use of ultrasonography in the intensive care unit, there is a renewed interest in sepsis-related myocardial dysfunction. This review summarises the current scope of literature focused on sepsis-related myocardial dysfunction and highlights the use of basic and advanced echocardiographic techniques for the diagnosis of sepsis-related myocardial dysfunction and the management of sepsis and septic shock.

A case of catastrophic antiphospholipid syndrome: first report with advanced cardiac imaging using MRI

This present case pertains to a 48-year-old woman with a history of antiphospholipid syndrome, who presented with progressive fatigue, generalized weakness, and orthopnea acutely. She had a prior diagnosis of antiphospholipid syndrome with recurrent deep vein thromboses (DVTs) and repeated demonstration of lupus anticoagulants. She presented in cardiogenic shock with markedly elevated troponin and global myocardial dysfunction on echocardiography, and cardiac catheterization revealed minimal disease. Cardiac magnetic resonance imaging was performed, which revealed findings of perfusion defects and microvascular obstruction, consistent with the pathophysiology of catastrophic antiphospholipid syndrome (CAPS). Diagnosis was made based on supportive imaging, including head magnetic resonance imaging (MRI) revealing multifocal, acute strokes; microvascular thrombosis in the dermis; and subacute renal infarctions. The patient was anticoagulated with intravenous unfractionated heparin and received high-dose methylprednisolone, plasmapheresis, intravenous immunoglobulin, and one dose each of rituximab and cyclophosphamide. She convalesced with eventual myocardial recovery after a complicated course. The diagnosis of CAPS relies on the presence of (1) antiphospholipid antibodies and (2) involvement of multiple organs in a microangiopathic thrombotic process with a close temporal association. The myocardium is frequently affected, and heart failure, either as the presenting symptom or cause of death, is common. Despite echocardiographic evidence of myocardial dysfunction in such patients, MRIs of CAPS have not previously been reported. This case highlights the utility in assessing the involvement of the myocardium by the microangiopathic process with MRI. Because the diagnosis of CAPS requires involvement in multiple organ systems, cardiac MRI is likely an underused tool that not only reaffirms the pathophysiology of CAPS, but could also clue clinicians in to the possibility of a diffuse thrombotic process.

Dynamic Phenotypes of Degenerative Myxomatous Mitral Valve Disease

Background—

Fibro-elastic deficiency (FED) and diffuse myxomatous degeneration (DMD) are phenotypes of degenerative mitral valve disease defined morphologically. Whether physiological differences in annular and valvular dynamics exist between these phenotypes remains unknown.

Methods and Results—

We performed triple quantitation of cardiac remodeling and of mitral regurgitation severity and of annular and valvular dimensions by real-time 3-dimensional-transesophageal-echocardiography. Forty-nine patients with degenerative mitral valve disease classified as FED (n=31) and DMD (n=18) by surgical observation showed no difference in age (65±10 versus 59±13; P =0.5), body surface area (2.0±0.2 versus 2.0±0.2 m 2 ; P =0.5), left ventricular and atrial dimensions (all P >0.55), and mitral regurgitation regurgitant orifice ( P =0.62). On average, annular dimensions were larger in DMD versus FED, but height was similar resulting in lower saddle shape. Dynamically, annular DMD versus FED display poorer contraction and saddle-shape accentuation in early systole and abnormal enlargement, particularly intercommissural, in late-systole (all P <0.05). Valvular dynamics showed stable valvular area in systole in FED versus considerable systolic increased area in DMD ( P <0.001). Prolapse height and volume increased little throughout systole in FED versus marked increase in DMD ( P <0.001).

Conclusions—

Our novel observations show that FED and DMD, although both labeled myxomatous, display considerable physiological phenotypic differences. In DMD, the annular increased size and profoundly abnormal dynamics demonstrate DMD-specific annular degeneration compared with the enlarged but relatively normal FED annulus. DMD does not incur more severe mitral regurgitation, despite larger prolapse and valve redundancy, underscoring potential compensatory role of tissue redundancy of DMD (or aggravating role of tissue paucity of FED) on mitral regurgitation severity.

Unveiling nonischemic cardiomyopathies with cardiac magnetic resonance

Cardiomyopathy is defined as a heterogeneous group of myocardial disorders with mechanical or electrical dysfunction. Identification of the etiology is important for accurate diagnosis, treatment and prognosis, but continues to be challenging. The ability of cardiac MRI to non-invasively obtain 3D-images of unparalleled resolution without radiation exposure and to provide tissue characterization gives it a distinct advantage over any other diagnostic tool used for evaluation of cardiomyopathies. Cardiac MRI can accurately visualize cardiac morphology and function and also help identify myocardial edema, infiltration and fibrosis. It has emerged as an important diagnostic and prognostic tool in tertiary care centers for work up of patients with non-ischemic cardiomyopathies. This review covers the role of cardiac MRI in evaluation of nonischemic cardiomyopathies, particularly in the context of other diagnostic and prognostic imaging modalities.

Severe sepsis and septic shock in patients with pre-existing non-cardiac pulmonary hypertension: contemporary management and outcomes

OBJECTIVE

To review treatment and outcomes of septic shock in patients with pulmonary hypertension (PH) managed at a tertiary care institution.

DESIGN, SETTING AND PATIENTS

We identified consecutive patients with non-cardiac PH (non-Group 2 in the World Health Organization classification) who were treated for septic shock in four intensive care units at a tertiary care institution between July 2004 and July 2007. Patients with a left ventricular ejection fraction < 50%, diastolic dysfunction, pericardial effusion or significant valve disease were excluded. Descriptive statistics were used to analyse the data.

MAIN OUTCOME MEASURES

Hospital mortality, duration of vasopressor and ventilatory support, length of hospital and ICU stay.

RESULTS

The final group for analysis comprised 82 patients. The major causes of PH were chronic obstructive pulmonary disease, interstitial lung disease and portopulmonary hypertension. PH was mild in 46 patients (56%), moderate in 21 (26%) and severe in 15 (18%). Vasopressor treatment was initiated in 69 patients (84%) within the first 48 hours: noradrenaline was most commonly used (53 patients, 65%), and 51 patients (62%) were treated with more than one agent. Sixty-seven patients (82%) were mechanically ventilated, and 33 (40%) required renal replacement therapy. Fortythree patients (52%) survived to hospital discharge; 23 (28%) remained alive at 1 year. Hospital mortality increased with severity of PH: 28% in mild, 67% in moderate and 80% in severe PH. Nonsurvivors were more likely to have plateau pressures beyond 30 cm H(2)O while mechanically ventilated within the first 48 hours in the ICU (56% v 29%, P = 0.03), to develop atrial fibrillation (AF) (46% v 12%, P < 0.001), and to require longer vasopressor support (mean, 5.3 v 2.6 days, P = 0.003). In a multivariate logistic regression analysis, severity of PH (odds ratio [OR], 1.55; 95% CI, 1.04-2.46; P = 0.04), new-onset AF (OR, 6.51; 95% CI, 2.24-22.07; P < 0.001) and longer duration of vasopressor support (OR, 1.15; 95% CI, 1.03-1.34; P = 0.04) were associated with increased hospital mortality.

CONCLUSIONS

The severity of PH, new-onset AF, and longer vasopressor support were associated with poor outcomes in patients with PH who developed severe sepsis and septic shock.

Real-time 3-dimensional dynamics of functional mitral regurgitation: a prospective quantitative and mechanistic study

Background

Three‐dimensional transthoracic echocardiography (3D‐TTE) with dedicated software permits quantification of mitral annulus dynamics and papillary muscle motion throughout the cardiac cycle.

Methods and Results

Mitral apparatus 3D‐TTE was acquired in controls (n=42), patients with left ventricle dysfunction and functional mitral regurgitation (LVD‐FMR; n=43) or without FMR (LVD‐noMR, n=35). Annulus in both normal and LVD‐noMR subjects displayed saddle shape accentuation in early‐systole (ratio of height to intercommissural diameter, 10.6±3.7 to 13.5±4.0 in normal and 9.1±4.3 to 12.6±3.6 in LVD‐noMR; P<0.001 for diastole to early‐systole motion, P=NS between those groups). In contrast, saddle shape was unchanged from diastole in FMR patients (10.0±6.4 to 8.0±5.2; P=NS, P<0.05 compared to both other groups). Papillary tips moved symmetrically towards to the midanterior annulus in control and LVD‐noMR subjects, maintaining constant ratio of the distances between both tips to midannulus (PtAR) throughout systole. In LVD‐FMR patients midsystolic posterior papillary tip to anterior annulus distance was increased, resulting in higher PtAR (P=0.05 compared to both other groups). Mechanisms of early‐ and midsystolic FMR differed between different etiologies of LV dysfunction. In patients with anterior MI and global dysfunction annular function and dilatation were the dominant parameters, while papillary muscle motion was the predominant determinant of FMR in patients with inferior MI.

Conclusions

Inadequate early‐systolic annular contraction and saddle‐shape accentuation in patients with impaired LV contribute to early–mitral incompetency. Asymmetric papillary tip movement towards the midanterior annulus is a major determinant of mid‐ and late‐systolic functional mitral regurgitation.

Electrophysiological and hemodynamic characteristics associated with obesity in patients with atrial fibrillation

OBJECTIVES

The authors sought to characterize the left atrial (LA) and pulmonary vein (PV) electrophysiological and hemodynamic features in obese patients with atrial fibrillation (AF).

BACKGROUND

Obesity is associated with increased risk for AF.

METHODS

A total of 63 consecutive patients with AF who had normal left ventricular (LV) ejection fraction and who underwent catheter ablation were studied. Atrial and PV electrophysiological studies were performed at the time of ablation with hemodynamic assessment by cardiac catheterization, and LA/LV structure and function by echocardiography. Patients were compared on the basis of body mass index (BMI): <25 kg/m(2) (n = 19) and BMI ≥30 kg/m(2) (n = 44).

RESULTS

At a 600-ms pacing cycle length, obese patients had shorter effective refractory period (ERP) in the left atrium (251 ± 25 ms vs. 233 ± 32 ms, p = 0.04), and in the proximal (207 ± 33 ms vs. 248 ± 34 ms, p < 0.001) and distal (193 ± 33 ms vs. 248 ± 44 ms, p < 0.001) PV than normal BMI patients. Obese patients had higher mean LA pressure (15 ± 5 mm Hg vs. 10 ± 5 mm Hg, p < 0.001) and LA volume index (28 ± 12 ml/m(2) vs. 21 ± 14 ml/m(2), p = 0.006), and lower LA strain (5.5 ± 3.1% vs. 8.8 ± 2.8%; p < 0.001) than normal BMI patients.

CONCLUSIONS

Increased LA pressure and volume, and shortened ERP in the left atrium and PV are potential factors facilitating and perpetuating AF in obese patients with AF.

Care of patients with acute pulmonary emboli: a clinical review with cardiovascular focus

Acute pulmonary embolism (PE) is a common, multidisciplinary disease with substantial associated morbidity, mortality and healthcare expense. In this article we present a succinct review of diagnostic tools, risk stratification and medical therapies for cardiovascular care of patients with acute PE. While pulmonary angiography remains the 'gold standard' for diagnosis, a host of diagnostic modalities, interpreted in the setting of clinical probability, are available for patient assessment, including ECG, chest radiography, D-dimer, lower-extremity venous ultrasound, ventilation-perfusion scans, computed tomography and magnetic resonance angiography, and echocardiography, each with associated value. Diagnostic algorithms incorporate multiple tools in order to obtain a more comprehensive evaluation. Therapeutic anticoagulation remains the mainstay of therapy in PE. In massive PE, utilization of thrombolysis is reasonable in the absence of contraindications. Submassive PE, characterized by right ventricular dysfunction as assessed by echocardiography and ECG, is associated with higher mortality. Use of thrombolysis in submassive PE remains controversial. Catheter-directed therapies are emerging as an added approach to acute PE and have the potential to improve outcomes in PE. Use of inferior vena cava filters should be pursued in a select patient population as they serve to reduce recurrent acute PE; however, they are associated with more frequent deep venous thrombosis and provide no mortality benefit. In risk-stratified hemodynamically stable patients, an outpatient management strategy inclusive of therapeutic anticoagulation and careful clinical follow-up may be appropriate.

Measuring Left Ventricular Ejection Fraction – Techniques and Potential Pitfalls

Prognosis and therapeutic decisions are often based on left ventricular ejection fraction (LVEF), which means the LVEF needs to be accurately measured. Many imaging modalities can measure LVEF. Each of these modalities is subject to measurement errors that can lead to the inaccurate calculation of LVEF. This article reviews the most common non-invasive imaging modalities – i.e., echocardiography, magnetic resonance imaging (MRI), computed tomography (CT), radionuclide angiography, gated myocardial perfusion single-photon emission computed tomography (SPECT) and gated myocardial perfusion positron emission tomography (PET) – used to measure LVEF, as well as the common sources of error with each of them. It is important to understand these sources of errors in order to prevent them, and recognise them when they do occur so that they can be corrected if possible.