Clinical utility of transoesophageal echocardiography in low resource environments: the Jamaican experience.

OBJECTIVE: To provide the first detailed review of the indications and clinical utility of transoesophageal echocardiogram (TEE) in the Caribbean. DESIGN AND METHODS: Data for patients who had TEE performed at the Heart Institute of the Caribbean over a three-year period were abstracted and reviewed. Information gathered included demographic data, indications for the procedure, findings and clinical recommendations. The effect of age and sex on these variables was assessed using the Chi-square or Fishers Exact tests. Significance was set at a p < or = 0.05. RESULTS: Of the 116 procedures performed between 2005 and 2008, medical records were reviewed for 107 (50 male, 57 female) patients. The patients ranged in age from 15-86 years with a mean age of 45.4 +/- 18.5 years. With the exception of four patients, all attempted TEE were completed. The most common indications for the procedure were valvular heart disease (41.1%), strokes (17.8%), shunts (10.3%) and infective endocarditis (11.2%). Less common indications included arrhythmias, cardiac masses, aortic dissection and shortness of breath. Transoesophageal echocardiogram altered the treatment course in about 30% of all patients including 66.6% of patients referred for suspected infective endocarditis. Furthermore, TEE resulted in recommendation for surgery in 43% of patients referred for evaluation of severity of valvular disease. Minor complications occurred in two persons. No severe complications or deaths occurred as a result of the procedure. CONCLUSIONS: Transoesophageal echocardiogram has been most commonly performed to evaluate valvular heart disease in Jamaica without any major complications resulting from the procedure. It provides additional information that supplements transthoracic echocardiography in a wide range of clinical conditions. Measures should be put in place to make TEE more widely available and accessible in Jamaica.

Left ventricular papillary muscle morphology and function in left ventricular hypertrophy and left ventricular dysfunction.

BACKGROUND: This study was prospectively performed to evaluate the anatomy and contractile performance of LV papillary muscles (PM) in humans using transesophageal echocardiography (TEE), and to determine the relationship between PM anatomy and contractile function in normal left ventricle (LV), left ventricular hypertrophy (LVH) and systolic dysfunction. MATERIAL AND METHODS: TEE examinations were prospectively performed in 153 patients. End-diastolic (ED) and end-systolic (ES) cross sectional areas of both PMs were obtained at the transgastric mid papillary short axis views. ED and ES lengths of PMs were obtained from the transgastric long axis views, and fractional systolic shortening (FS) was calculated. PM shape description was derived from the formula Area/L2. LV EF, wall thickness and mass were determined from transthoracic echocardiographic measurements. RESULTS: The % FS in patients with normal EF (>55%) was 21.1 +/- 9.1% for anterior PM (APM) and 17.1 +/- 6.2% for posterior PM (PPM). The values for hypertrophic LV were as follows; 25.2 +/- 8.1 (APM) and 15.8 +/- 5.6 (PPM), for dilated cardiomyopathy, 15.0 +/- 6.8 (APM) and 13.4 +/- 4.2 while values for non-dilated cardiomyopathy were 15.6 +/- 8.0 and 11.3 +/- 6.0 respectively. In dilated cardiomyopathy patients, both PM lengths were significantly longer (p<0.05) and thinner (p<0.05) than in patients with normal EF. In the hypertrophied LV, the PMs were thicker (p<0.05) and had larger cross sectional areas p<0.05. CONCLUSIONS: TEE is a safe and useful method for detailed study of PM morphology and contractile performance in living humans with normal or impaired LV systolic function. Quantitative TEE data on PM geometry, size, and contractile function are presented here for the first time.

Effect of ethnicity and hypertension on atrial conduction: evaluation with high-resolution P-wave signal averaging.

BACKGROUND: Measurements by P-wave signal-averaged electrocardiogram (P-SAECG) of P-wave duration and P-wave voltage integral are higher in patients with atrial fibrillation (AF) than in those with sinus rhythm. Hypertension is perhaps the most common cardiovascular antecedent cause of AF, and particularly a disproportionate cause of morbidity and mortality among blacks. The purpose of this study was to examine the effect of hypertension and ethnicity on P-SAECG parameters in patients without AF. HYPOTHESIS: It was hypothesized that P-SAECG parameters can identify hypertensives, and are disproportionately higher in hypertensive blacks. METHODS: In all, 234 normotensives and 84 hypertensives underwent P-SAECG analysis. In an ancillary study group of 34 hypertensive black men, the relationship between severity of hypertension and measured parameters of P-SAECG was evaluated. RESULTS: Mean filtered P-wave duration and total P-wave voltage integral for normotensives of both ethnic groups were similar. Hypertensive blacks had greater increase in P-wave duration (138 +/- 16 vs. 132 +/- 12ms;p < 0.01, N42:42) and total P-wave voltage integral (922 +/- 285 vs. 764 +/- 198 microV-ms; p < 0.001) than white hypertensives. Filtered P-wave duration and total P-wave voltage integral increased with severity of hypertension. CONCLUSIONS: Patients at very early stages of hypertension have demonstrable evidence of prolonged atrial conduction by P-SAECG and, thus, cardiac electrical remodeling. P-wave duration and total P-wave voltage integral increase with severity of hypertension. Hypertensive blacks manifest a greater increase in P-SAECG parameters than whites. This may portend an increased cardiovascular risk for black patients with hypertension.

Recurrent ischemia resulting from left internal mammary artery-to-pulmonary artery fistula.

This report describes a case series of recurrent ischemia after coronary artery bypass grafting resulting from left internal mammary artery-to-pulmonary artery fistula. An angiographic demonstration of this fistula is presented.

Papillary muscle contribution to ventricular ejection in normal and hypertrophic ventricles: a transesophageal echocardiographic study.

BACKGROUND: The interrelationship between left ventricular (LV) volume, stroke volume, and papillary muscle (PM) volume have not been studied. These volumes are relevant in understanding LV ejection mechanics in normal chambers and ascertaining whether differences exist between normal and hypertrophied LV chambers. METHODS AND RESULTS: PM basal areas were measured in short-axis transesophageal echocardiographic views and lengths were measured in long-axis views. PM volume was estimated by the formula for volume of a cone: 1/3 x PM base area x PM length. The formula for LV volume was as follows: LV volume = 2/3 x LV area x LV length. Of the initial 82 subjects with normal LV function studied by TEE, data on 71 are presented in this report. Thirty-two patients had normal LV size and wall thickness, and 39 had LV hypertrophy (LVH). PM volume/LV volume % in end-diastole (ED) and end-systole (ES) in normal muscles was 3.1 +/- 1.0 and 9.6 +/- 4.9, respectively. In LVH, the respective values were 5.1 +/- 2.0 (P < 0.05) and 13.5 +/- 4.9 (P < 0.05). For those with severe LVH, the values were 7.1 +/- 2.5 (P < 0.001) and 15.9 +/- 4.1 (P < 0.001), respectively, for ED and ES. Similar trends were seen in the PM volume/stroke volume relationships in normal and hypertrophic ventricles. CONCLUSIONS: PMs are larger and form a larger fraction of LV volume in LVH than in normal muscles. In patients with severe LVH, the contribution of PMs to ventricular ejection is more pronounced. PMs may, therefore, play a larger role in LV ejection in LVH than in normal ventricles (i.e., hypertrophied PM enhance the pump efficiency of LV ejection).

Transesophageal echocardiographic spectrum of calcific mitral abnormalities in patients with end-stage renal disease.

This report provides a morphological description of atypical and unusual mitral and submitral calcifications in patients with end-stage renal disease. The use of transesophageal echocardiography (TEE) with enhanced image quality and resolution has made possible a detailed evaluation of the distribution and echocardiographic morphology of mitral calcification in end-stage renal disease. To our knowledge, there has been no such prior report with TEE. Our TEE observations reveal that in addition to the common well known posterior mitral annulus calcification, the following varieties of calcification also exist: basal calcification of both mitral leaflets with sparing of free edges, calcification in the intervalvular fibrosa region, and small calcific excrescences at the bases of both mitral leaflets. These abnormalities have previously received little or no attention.

Transesophageal dobutamine stress echocardiography in the evaluation of myocardial ischemia in morbidly obese subjects.

BACKGROUND: The evaluation of chest pain or suspected coronary artery disease (CAD) in morbidly obese subjects is limited by the inability of routine diagnostic techniques to adequately image these individuals. Morbidly obese subjects are therefore often inadequately treated or inappropriately treated for presumed CAD. METHODS AND RESULTS: We prospectively evaluated 23 morbidly obese patients with chest pain using transesophageal dobutamine stress echocardiography (TE-DSE). The mean (+/- SD) weight was 164 +/- 8 kg (range, 118 to 215 kg). We identified nine patients with abnormal TE-DSE findings. Five of these patients subsequently had cardiac catheterization with confirmation of CAD in the regions identified by TE-DSE. Over a follow-up period of 18 +/- 6 months, three cardiac events (non-Q-wave myocardial infarction) occurred in the same group, including two patients without confirmatory cardiac catheterization data. Thus, seven of nine patients with positive results of TE-DSE had objective confirmatory evidence of CAD. No cardiac events were observed in the group with normal TE-DSE over the same follow-up period. CONCLUSION: TE-DSE is a safe and potentially useful technique for the evaluation of suspected CAD in morbidly obese subjects.

Crack-cocaine-associated aortic dissection in early pregnancy--a case report.

Even though uncommon in pregnancy, aortic dissection is a potentially catastrophic vascular complication, occurring mainly in the late stages of pregnancy. Vascular events, including aortic dissection are recognized complications of crack-cocaine use. The authors report a case of aortic dissection in early pregnancy related to crack-cocaine use. They believe that the combined effects of pregnancy and crack cocaine on the vasculature create the requisite milieu potentiating such catastrophic events as aortic dissection. This paper reviews the possible underlying pathophysiologic mechanisms and the available diagnostic, therapeutic, and management options.

Role of transesophageal echocardiography in the clinical management of a patients with a giant coronary artery aneurysm.

Transthoracic echocardiography (TTE) has substantial limitations for the study of abnormalities of the coronary tree. Transesophageal echocardiography (TEE) allows a more complete examination of the coronary arteries, particularly the proximal segments. This report describes the use of TEE after cardiac catheterization in the clinical management of a patient with unstable angina. While angiography first showed the giant aneurysm of the left circumflex coronary artery. TEE, by revealing an active thrombus of the lumen, prompted an immediate surgical resolution.

Dynamic left ventricular outflow tract obstruction in critically ill patients: role of transesophageal echocardiography in therapeutic decision making.

A paradoxic hypotensive response to resuscitative treatment may be the first clue to dynamic left ventricular outflow tract obstruction (DLVOTO) in critically ill patients. If unrecognized, routine interventions aimed at improving cardiac performance may actually result in hypotension and low cardiac output, thus putting patients at risk for adverse event. It is imperative, therefore, that the pathophysiologic processes involved in DLVOTO be fully understood in order to initiate safe and appropriate therapy in critically ill patients. Our presentation and discussion focus on a hypotensive critically ill patient with unrecognized DLVOTO until further evaluation with transesophageal echocardiogram (TEE). We recommend that early TEE be performed on critically ill patients with unexplained hypotension that is poorly responsive to conventional resuscitative measures.

Reproducibility of exercise-induced modulation of cardiovascular responses to cold stress.

The modulation of cardiovascular responses to the cold pressor test (CPT) as produced by exercise was studied in 13 volunteers. The reproducibility of the measurements selected for the study, i.e. heart rate (HR), blood pressure (BP), blood flow (BF) and skin temperature (ST), was investigated through repeat experiments in the fall of 1994 and the winter of 1995. HR was monitored before, during and after a 10-min period of bicycling at 70% of reserve HR. BP, cutaneous BF and ST were measured before and after exercise. Two CPTs (hand into ice-cold water for 1 min) were performed: one preceding exercise and another at 3 min after exercise. The results obtained allow us to conclude that in non-hypertensive volunteers (1) the pronounced cardiovascular responses (ST, BF and BP) induced by CPT are reproducible (p > 0.2) when compared to basal level values and (2) cardiovascular responses to cold stress are significantly attenuated by exercise (p < 0.03). Our study, therefore, supports and validates the use of our coupled exercise-CPT method in ongoing epidemiological studies attempting to identify individuals at risk for the development of hypertension as well as those most likely to benefit from preventative exercise programs.

The vital role of papillary muscles in mitral and ventricular function: echocardiographic insights.

The two left ventricular (LV) papillary muscles are small structures but are vital to mitral valve competence. Partial or complete rupture, complicating acute myocardial infarction, causes severe or even catastrophic mitral regurgitation, potentially correctable by surgery. Papillary muscle dysfunction is a controversial topic in that the role of the papillary muscle itself, in causing mitral regurgitation post infarction, has been seriously questioned; it is less confusing if this syndrome is attributed not only to papillary muscle but also to adjacent LV wall ischemia or infarction. Papillary muscle calcification is easily and frequently detected on echocardiography, but its clinical significance remains uncertain. Papillary muscle hypertrophy accompanies LV hypertrophy of varied etiology and may have a significant role in producing dynamic late-systolic intra-LV obstruction in hypertrophic cardiomyopathy and other hyperdynamic hypertrophied LV chambers. All the above abnormalities can be adequately assessed by 2-D echocardiography and the Doppler modalities. In selected cases, transesophageal echocardiography can provide additional valuable data by improving visualization of papillary muscles and mitral apparatus.

Case report: Candida zeylanoides infective endocarditis complicating infection with the human immunodeficiency virus.

Despite the frequent occurrence of mucosal candidiasis in patients infected with HIV, systemic candidiasis is uncommon and usually associated with intravenous catheters, parenteral nutrition, or antibiotics and neutropenia. Most of the fungal isolates are usually Candida albicans, Candida tropicalis or Candida parapsilosis. The authors report a case of infective endocarditis due to Candida zeylanoides that occurred in a patient infected with HIV in the absence of the usual risk factors for systemic candidiasis.

Review: the effects of antihypertensive agents on serum lipids.

Because various antihypertensive drugs adversely affect lipid metabolism, these drugs may increase associated risks for coronary artery disease and thus offset some of the beneficial effects of blood pressure reduction. In this paper the current literature regarding the effects of antihypertensive agents on serum lipids is reviewed. Differing effects of various classes of antihypertensives are assessed to further our understanding of this very important subject.

Sustained nonischemic ventricular tachycardia during dobutamine stress echocardiography.

Dobutamine stress echocardiography has become widely accepted as a safe, reliable and cost effective modality for the evaluation of patients with suspected myocardial ischemia or for prognostic stratification and outcome assessment in patients with known coronary artery disease. while the benefits of this means of cardiovascular testing are very clearly apparent, it is important to understand and recognize possible complications. This paper discusses the occurrence of sustained, nonischemic ventricular tachycardia during dobutamine stress echocardiography in the absence of functional, physiologic or anatomic evidence of coronary artery disease or cardiomyopathy.

Progression to calcific mitral stenosis in end-stage renal disease.

A 59-year-old man with end-stage renal disease and on hemodialysis had neither mitral stenosis nor mitral calcification on echo-Doppler examination in 1989, but had extensive mitral calcification and definite mitral stenosis on conventional and transesophageal echocardiography in 1994. The left ventricle had marked concentric hypertrophy. To our knowledge this is the first documentation of the development of calcific mitral stenosis in end-stage renal disease revealed by serial echo-Doppler studies.

Two-vessel coronary artery dissection in the peripartum period. Case report and literature review.

The authors report a case of early peripartum myocardial infarction resulting from spontaneous dissection of the left anterior descending coronary artery and right coronary artery in a twenty-four-year-old woman. This is the first report of double-vessel coronary dissection involving both the left and right coronary arteries diagnosed antemortem and successfully treated.

Clinical utility of digital dobutamine stress echocardiography in the noninvasive evaluation of coronary artery disease.

Exercise electrocardiography is an established mode of evaluation for patients with suspected coronary artery disease. It also provides prognostic information and guides therapeutic management in patients with established disease. However, some patients are unable to exercise because of orthopedic problems, neurologic diseases, peripheral vascular disease, or deconditioning. In the past, these patients have been referred for angiography to help assess their disease. Recently, however, new techniques to assess myocardial perfusion and/or function, including stress echocardiography, have been used in the noninvasive assessment of coronary artery disease in this group of patients. Echocardiography has been used in combination with different drugs, including dobutamine, dipyridamole, and adenosine. Dobutamine is probably the single most studied drug for stress echocardiography. Dobutamine stress echocardiography is a safe, feasible, and valuable technique for evaluating coronary artery disease.