PubMed Health⌕ Search

Biomedical subjects

Dennis A Tighe

Publications and source records attributed to Dennis A Tighe.

15 recordsLinked to original sources

Echocardiography and reversible left ventricular dysfunction.

PURPOSE: Transient apical ballooning is increasingly recognized in acutely ill, hospitalized patients. This article reviews clinical aspects of the syndrome, its recognition by echocardiography, and will review other disorders whose recognition is due primarily to the availability of echocardiography. METHODS: Systematic review of the medical literature concerning the syndrome of transient apical ballooning. RESULTS: Seven recent studies of transient apical ballooning are reviewed; the clinical characteristics, biomarker data, echocardiographic findings, and angiographic data are remarkably similar. Most afflicted individuals are women in their seventh decade who develop chest symptoms in close relationship to a "trigger" event--this is usually either severe emotional distress, a medical illness, or a procedure. CONCLUSIONS: Transient apical ballooning is not uncommonly encountered among acutely ill, hospitalized patients with chest symptoms. As yet there is no consensus of the underlying mechanism, although there is reason to believe that catecholamine injury to the myocardium is partially, if not wholly responsible. The widespread use of echocardiography appears to be responsible for the increasing recognition of this (and other) syndromes.

Catecholamines↗

An unusual cause of pulmonary vein stenosis: a case report and review of the literature.

We describe the case of a patient with the Carney syndrome and several resections for recurrent left atrial myxomas who underwent autotransplantation of the heart with resection of the left and right atria and reconstruction of both atria with bovine pericardium. She subsequently presented with severe shortness of breath, ascites, and peripheral edema. She was found to have stenosis of all four pulmonary veins and severe pulmonary hypertension. We describe the echocardiographic findings and review the literature on assessment of acquired pulmonary vein stenosis.

Cardiac Surgical Procedures↗

Calculated low density lipoprotein cholesterol levels frequently underestimate directly measured low density lipoprotein cholesterol determinations in patients with serum triglyceride levels < or =4.52 mmol/l: an analysis comparing the LipiDirect magnetic LDL assay with the Friedewald calculation.

BACKGROUND: Increased low density lipoprotein cholesterol (LDL-C) is an established risk factor for the development of coronary artery disease (CAD). Recent guidelines detail specific LDL-C cutpoints for therapeutic goals. In practice, LDL-C is usually derived from the Friedewald formula (FF). This calculation is known to be inaccurate with serum triglyceride (TG) concentrations >4.52 mmol/l, however, its accuracy among relatively healthy patient cohorts with TG concentrations < or =4.52 mmol/l is less well studied. METHODS: We studied 661 ambulatory adults with TG concentrations < or =4.52 mmol/l and no overt CAD. Fasting venous lipid panels were obtained. LDL-C was calculated from the FF and also directly measured with the LipiDirect Magnetic LDL assay. Linear regression and paired t-test analyses were performed. RESULTS: Calculated and directly measured LDL-C concentrations were significantly different (4.26+/-0.88 vs. 4.83+/-1.06 mmol/l respectively, p<0.0001). In 93% of measurements directly measured LDL-C exceeded calculated LDL-C. Although calculated and directly measured LDL-C concentrations were related (R=0.90), the discrepancy between them increased linearly with increasing TG concentrations (R=0.67) and clinically important differences existed at normal or slightly increased TG concentrations. Concordant results for NCEP ATP-III risk categories were present for only 48.1% of samples. CONCLUSIONS: Significant differences between calculated and directly measured LDL-C using the LipiDirect Magnetic LDL assay exist in healthy subjects with TG < or =4.52 mmol/l. These differences are linearly related to TG concentrations and occur frequently at relatively low TG concentrations.

Adult↗

Analysis of left ventricular systolic function using midwall mechanics in patients >60 years of age with hypertensive heart disease and heart failure.

Normal ejection fraction (EFs) is often equated with normal systolic function. However, midwall mechanics reveal systolic dysfunction in hypertensive heart disease accompanied by hypertrophic remodeling. Midwall mechanics are unstudied in patients with acute diastolic heart failure (HF). This study analyzed left ventricular (LV) midwall stress-shortening relations in 61 patients aged >60 years with hypertensive heart disease, HF, and normal EF. Sixty-one hypertensive patients (mean age 78 +/- 10 years) who presented with HF, each with an EF >50%, underwent echocardiography. Midwall mechanics were compared with those of 79 controls (mean age 75 +/- 8 years) without structural heart disease. Relative wall thickness (0.63 +/- 0.11 vs 0.46 +/- 0.10 mm) and LV mass (237 +/- 67 vs 177 +/- 57 g) were significantly greater in patients with HF compared with controls. Mean EFs were similar in patients with HF and controls (64 +/- 9% vs 67 +/- 9%). Although mean endocardial fractional shortening (35 +/- 7% vs 37 +/- 7%) was not significantly different, midwall shortening in patients with HF was significantly less compared with controls (16 +/- 2% vs 19 +/- 3%, p <0.05). Eighteen of the 61 patients with HF (30%) had midwall shortening that was <95% confidence intervals of the normal midwall stress-shortening relations. By this criterion, these patients had systolic dysfunction despite normal EF; they had smaller LV chambers (in dimension and volume), greater relative wall thickness, and smaller stroke volumes. In conclusion, almost 1/3 of patients hospitalized with diastolic HF had systolic dysfunction, characterized by abnormal midwall stress-shortening relations.

Aged↗

Catheterization-Doppler discrepancies in nonsimultaneous evaluations of aortic stenosis.

Prior validation studies have established that simultaneously measured catheter (cath) and Doppler mean pressure gradients (MPG) correlate closely in evaluation of aortic stenosis (AS). In clinical practice, however, cath and Doppler are rarely performed simultaneously; which may lead to discrepant results. Accordingly, our aim was to ascertain agreement between these methods and investigate factors associated with discrepant results. We reviewed findings in 100 consecutive evaluations for AS performed in 97 patients (mean age 72 +/- 10 yr) in which cath and Doppler were performed within 6 weeks. We recorded MPG, aortic valve area (AVA), cardiac output, and ejection fraction (EF) by both methods. Aortic root diameter, left ventricular end-diastolic dimension (LVIDd) and posterior wall thickness (PWT) were measured by echocardiography and gender, heart rate, and heart rhythm were also recorded. An MPG discrepancy was defined as an intrapatient difference > 10 mmHg. Mean pressure gradients by cath and Doppler were 36 +/- 22 mmHg and 37 +/- 20 mmHg, respectively (P = 0.73). Linear regression showed good correlation (r = 0.82) between the techniques. An MPG discrepancy was found in 36 (36%) of 100 evaluations; in 19 (53%) of 36 evaluations MPG by Doppler was higher than cath, and in 17 (47%) of 36, it was lower. In 33 evaluations, EF differed by >10% between techniques. Linear regression analyses revealed that EF difference between studies was a significant predictor of MPG discrepancy (P = 0.004). Women had significantly higher MPG than men by both cath and Doppler (43 +/- 25 mmHg versus 29 +/- 15 mmHg [P = 0.001]; 42 +/- 23 mmHg versus 32 +/- 15 mmHg [P = 0.014], respectively). Women exhibited discrepant results in 23 (47%) of 49 evaluations versus 13 (25%) of 51 evaluations in men (P = 0.037). After adjustment for women's higher MPG, there was no statistically significant difference in MPG discrepancy between genders (P = 0.22). No significant interactions between MPG and aortic root diameter, relative wall thickness (RWT), heart rate, heart rhythm, cardiac output, and time interval between studies were found. In clinical practice, significant discrepancies in MPG were common when cath and Doppler are performed nonsimultaneously. No systematic bias was observed and Doppler results were as likely yield lower as higher MPGs than cath. EF difference was a significant predictor of discrepant MPG. Aortic root diameter, relative wall thickness, heart rate, heart rhythm, cardiac output, presence or severity of coronary artery disease, and time interval between studies were not predictors of discrepant results.

Aged↗

Brain natriuretic peptide levels fall rapidly after cardioversion of atrial fibrillation to sinus rhythm.

BACKGROUND: Brain natriuretic peptide (BNP) levels have been reported to fall following cardioversion of atrial fibrillation (AF). The mechanism for the fall in BNP has not been elucidated and the potential confounding effects of sedation have not been investigated. Sedation may alter BNP levels via its effects on loading conditions. Accordingly, we studied whether BNP levels change shortly after cardioversion and attempted to control for possible effects of sedation. METHODS: BNP levels were obtained before and after cardioversion in patients with AF and in a control group of patients undergoing intravenous conscious sedation for transesophageal echocardiography. RESULTS: BNP levels dropped (260 +/- 255 vs. 190 +/- 212 pg/ml, p < 0.05) 40 min after cardioversion, decreasing in 33 of 41 subjects who achieved sinus rhythm. By contrast, mean BNP did not fall in subjects in whom cardioversion was not successful. The change in BNP level was not related to the degree of change in heart rate. No control subject experienced a change in cardiac rhythm; BNP levels increased (195 +/- 407 vs. 238 +/- 458 pg/ml, p < 0.05) in 18/22 subjects after sedation. Baseline BNP levels were elevated in subjects with AF, and BNP levels were elevated in parallel with heart failure symptoms. CONCLUSIONS: The rapid fall in BNP after cardioversion (1) may reflect prompt hemodynamic improvement associated with rhythm change and (2) does not appear to be due to the effects of sedation.

Adult↗

The utility of newly derived Doppler echocardiographic variables in the diagnosis and management of patients with heart failure.

Doppler echocardiography, because of its noninvasive nature, is an ideal tool to evaluate patients with heart failure (HF), offering the potential to improve early identification and management of these patients. Although traditional Doppler indices have allowed characterization of diastolic filling abnormalities associated with various HF states, important limitations are recognized. More refined Doppler techniques such as analysis of color M-mode flow propagation velocity, tissue Doppler imaging, and strain parameters can add to the ability of the noninvasive laboratory to improve the identification and management of this group of patients. These newer techniques as well as the traditional Doppler assessment of transmitral left ventricular inflow and pulmonary venous inflow velocities are reviewed as methods to improve the diagnosis and management of patients with HF.

Blood Flow Velocity↗

Paradoxical changes in brain natriuretic peptide levels and loading conditions after intravenous conscious sedation.

BACKGROUND: Elevated filling pressure and wall stress have been proposed as stimuli for elevated brain natriuretic peptide (BNP) levels. Narcotic and benzodiazepine sedation, such as is used for transesophageal echocardiography (TEE), is known to decrease filling pressures. We hypothesized that lower filling pressure and wall stress associated with intravenous conscious sedation (IVCS) would lead to lower BNP levels. METHODS: We studied BNP levels, blood pressure, and echocardiographic indices of filling pressure and wall stress before and after IVCS and TEE. RESULTS: When data before and after IVCS and TEE were compared, mean blood pressure decreased (149 +/- 24/83 +/- 14 mm Hg vs 126 +/- 29/69 +/- 14; P < .01), as did mitral Doppler E wave velocity (82 +/- 23 cm/s vs 76 +/- 22; P < .05), right ventricular/atrial gradient (31 +/- 10 mm Hg vs 29 +/- 13; P < .05), and wall stress. However, BNP levels increased (195 +/- 407 pg/mL vs 238 +/- 458; P < .01). CONCLUSIONS: In a series of patients undergoing clinically indicated TEE, BNP levels increase above baseline after IVCS. The increase in BNP occurs despite lower blood pressure, lower mitral Doppler E velocity, lower right ventricular/atrial gradient, and lower wall stress compared with baseline. The mechanism of the paradoxical increase in BNP is not entirely clear, but it may conceivably be a result of counterregulatory hormone release caused by acute decrease in blood pressure.

Adult↗

A syndrome of transient left ventricular apical wall motion abnormality in the absence of coronary disease: a perspective from the United States.

BACKGROUND: The syndrome of chest pain associated with characteristic anterior electrocardiographic changes, moderate increases in cardiac enzymes, and a reversible apical wall motion abnormality in the absence of coronary artery disease has been documented in Japan, but has received relatively little attention in other countries. METHODS: The clinical and echocardiographic data of 12 patients (11 women, mean age 64 +/-14 years) who presented with chest symptoms, electrocardiographic (ECG) changes indicative of an acute anteroapical myocardial infarction, abnormal cardiac enzyme levels and echocardiography showing an apical wall motion abnormality were collected. Coronary angiography was performed in 10 patients. A follow-up echocardiogram was obtained within 2 weeks of the initial diagnosis in most cases. RESULTS: An identifiable, precipitating ("trigger") event could be identified in all 12 individuals. Respiratory distress was present in 7, the death of a relative in 3, in 4 a surgical or medical procedure had been performed, and in 1 a panic disorder was diagnosed. The echocardiograms showed a characteristic wall motion pattern of significant apical dysfunction. All of the patients who underwent coronary arteriography had noncritical coronary artery disease. Follow-up echocardiography showed normalization of the LV dysfunction in all instances. CONCLUSION: We identified a syndrome of chest pain, dyspnea, ECG and enzyme changes mimicking acute myocardial infarction, similar to the "Takotsubo" syndrome described in Japan. It is likely that the widespread use of echocardiography, coupled with increased recognition of this syndrome, will result in this diagnosis being made more commonly.

Adrenergic beta-Antagonists↗

The hemodynamic signs of constrictive pericarditis can be mimicked by tricuspid regurgitation.

A case with clinical and hemodynamic findings consistent with constrictive pericarditis is reported. At surgery, the pericardium was not thickened or adherent to the epicardial wall. As suggested by echocardiography, a diagnosis of severe tricuspid regurgitation was confirmed. This case illustrates that invasive hemodynamic findings consistent with a picture of pericardial constriction can be produced by processes other than constrictive pericarditis.

Aged↗