Diabetic cardiomyopathy: an educational review.

This educational review provides information about the epidemiology of diabetes and heart failure (diabetic cardiomyopathy) and the challenges in diagnosis and screening. Details on how to investigate patients with imaging and other modalities are discussed, as well as an update regarding the efficacy and safety of novel agents for treatment of diabetic cardiomyopathy.

A tale of comet tail: multiple pellets in the heart.

A 66-year-old man who presented with chest pain was assessed with a CT coronary angiogram that showed multiple hyperdense bodies. Echocardiography documented a comet tail artefact, an uncommon ultrasonic finding but no other abnormality.

Impairment of autonomic reactivity is a feature of heart failure whether or not the left ventricular ejection fraction is normal.

BACKGROUND: Autonomic dysfunction (AD) is associated with morbidity and mortality in patients with systolic heart failure (SHF). The extent of AD when LV ejection fraction is preserved (HF-NEF), is unclear. Our objectives were: 1) quantitative assessment of autonomic function in SHF and HF-NEF; and 2) exploration of relationships among AD, symptoms and cardiac function. METHODS: This was an observational study of patients newly referred from primary care with a heart failure diagnosis; 21 SHF, 20 HF-NEF patients and 21 normal subjects were recruited. All subjects underwent clinical evaluation, 6-minute walk test (6 MWT), Minnesota Questionnaire (MLWHFQ) and echocardiography. Autonomic assessment included haemodynamic responses to standing, deep breathing and handgrip. Concomitant blood pressure variability (BPV) and heart rate variability (HRV) parameters were also derived. RESULTS: There were significant differences in all haemodynamic responses between SHF, HF-NEF and normal. Log transformed (ln) low frequency spectral component of BPV was lower in SHF (4.1 ± 0.3) than HF-NEF (4.2 ± 0.4) and normal (4.4 ± 0.1; p=0.001 SHF vs HF-NEF and vs normal). Ln LF/HF was greater in normal than HF-NEF and SHF (1.5 ± 0.7 vs 0.9 ± 1.0 vs 0.6 ± 0.6; p=0.003). Autonomic modulations correlated negatively with severity of heart failure. CONCLUSIONS: Autonomic responses in heart failure were blunted and the attenuation of responses correlated strongly with symptomatic and functional markers of disease severity. Autonomic dysfunction is a feature of the heart failure syndrome but is not dependent on ejection fraction.

Effects of remote ischemic preconditioning on the flow pattern of the left anterior descending coronary artery in normal subjects.

Remote ischemic preconditioning (RIPC) has been proposed as an effective method to improve both myocardial and vascular protection in human beings. The aim of this study was to identify the effect of RIPC on the flow pattern of left anterior descending coronary artery (LAD) by transthoracic Doppler echocardiography. 18 normal male volunteers were enrolled to this study. The Doppler signals of flow velocity were recorded at baseline, 1, 3, 6 and 9 min after reperfusion of each cycle to identify the effect of RIPC on the flow pattern of the LAD. In the study, the coronary mean velocity, peak diastolic velocity and mean diastolic velocity were increased (all P<0.05) in the first 3 min of reperfusion of each cycle while peak systolic velocity, mean systolic velocity and heart rate did not change compared with the baseline readings throughout RIPC. And the maximal coronary flow velocity was observed at the first minute of the second reperfusion. The result of this study proves that remote ischemic preconditioning produces hyperemia via the LAD during early reperfusion, which is characterized by an increase in diastolic flow velocity.

The prognostic significance of horizontal plane QRS axis in elderly heart failure.

In order to investigate whether horizontal plane QRS axis predicts the prognosis in elderly heart failure, we studied 80 consecutive patients by clinical assessment, ECG, Doppler and echocardiography. All patients were followed up for 2 years, 12 died and 68 survived. Age, gender distribution, blood pressure, co-existing diagnoses and medication were all similar between those who died and those who survived. The NYHA classification was significantly worse, left ventricular (LV) cavity size was greater, LV systolic function was lower in those who died than in survivors, despite similar LV wall thickness. On ECG, heart rate, PR interval, QT interval and frontal QRS axis did not differ between the two groups. The QRS duration was significantly longer and the horizontal QRS axis projected to a substantially more posterior direction in those who died than in survivors. The sensitivity and specificity of a horizontal QRS axis < or =-30 degrees for predicting death in 2 years were 75% and 62%, respectively. The former is above the sensitivity of a NYHA > or =3 and the latter is above the specificity of a LV shortening fraction < or =20%. The combination of a QRS horizontal axis < or =-30 degrees and NYHA > or =3 predicted 2 year mortality with a sensitivity of 75% and specificity of 91%. In conclusion, a left posterior QRS axis of the horizontal plane in elderly heart failure indicates an adverse prognosis, particularly when combined with NYHA classification and echocardiographic assessment.

Abnormal regional left ventricular mechanics in treated hypertensive patients with 'normal left ventricular function'.

Global systolic and diastolic LV function assessed by conventional echocardiographic indices is often normal in patients with controlled hypertension, with or without left ventricular hypertrophy. However, it is not certain whether regional myocardial function in these patients remains normal. We investigated 26 patients and 10 age matched normal controls, by means of long axis M-mode echocardiography. There was no significant difference in age, sex distribution, heart rate, blood pressure and routine ECG measurements between the two groups. Although there was significant LVH in patients compared to normal controls, LV cavity size and global systolic function, assessed by shortening fraction, ejection fraction and mean velocity of circumferential fibre shortening did not differ between the two groups, nor did LV diastolic function, assessed by the mitral flow pattern. However, LV regional mechanics, as assessed by multiple long axis M-mode echocardiograms differed significantly, in both systole and diastole, between the two groups. Compared to controls, the total longitudinal systolic excursion in both LV free wall and ventricular septum were significantly reduced in patients, and so was maximum early relaxation and atrial contraction in the LV free wall. The mean rate of systolic excursion in all 3 sites did not differ between the two groups, but the mean rate of early relaxation in both LV free wall and ventricular septum was significantly decreased in patients compared to normal controls. In conclusion, the evaluation of LV dysfunction in patients who have achieved good blood pressure control requires more than a conventional echocardiographic assessment. The assessment of regional mechanics described in the present paper offers an easy and sensitive method for the detection of subtle signs of LV mechanical inefficiency associated with LVH.

The association of chronic atrial fibrillation with right atrial dilatation and left ventricular dysfunction in the elderly.

BACKGROUND: Left atrial dilatation is often considered as one of the important causes for atrial fibrillation. In this study we sought to examine the relationship between right atrial dilatation and left ventricular function in patients with atrial fibrillation, and the association with the documented duration of the dysrrhythmia. MATERIAL/METHODS: 56 consecutive patients with atrial fibrillation were investigated by means of clinical history, electrocardiography and echocardiography. RESULTS: Right atrial dilatation was found in 34, left atrial dilatation in 36 and bi-atrial dilatation in 31 patients. Patients with a dilated right atrium had a larger left atrium, lower left ventricular shortening fraction, and higher transmitral flow velocity than those with a normal right atrium. A history of atrial fibrillation of over 6 months was associated with enlarged atria, reduced left ventricular shortening fraction and increased transmitral flow compared to that of 3 months or less. Functional mitral and tricuspid regurgitation were only found in patients whose atrial fibrillation was over 6 months in duration. CONCLUSIONS: Dilatation of both right and left atria is common in chronic atrial fibrillation, and is associated with impaired left ventricular function. A longer duration of atrial fibrillation predisposes to atrial dilatation, left ventricular dysfunction, and functional atrio-ventricular regurgitation. These findings suggest that atrial fibrillation may have a significant contribution to morphological and functional cardiac changes, and raise the possibilities that early cardioversion or adequate rate control might prevent these changes and may improve prognosis in the elderly.

Septal q waves as an indicator of risk of mortality in elderly patients with chronic heart failure.

BACKGROUND: The absence of electrocardiographic septal q wave is a recognized marker of left ventricular disease. We aimed to investigate the prognostic significance of absent septal q waves in elderly (age >65 years) patients with chronic heart failure. METHODS: A total of 110 patients (mean age 73 +/- 4 years) with New York Heart Association functional class II to IV and left ventricular ejection fraction of <45% were enrolled in the study. Standard 12-lead electrocardiograms were critically analyzed for the presence or absence of septal q waves in leads I, aVL, V5, and V6. Patient survival was determined from hospital and general practitioner records and National Statistics Registry at a mean follow-up of 4 years. RESULTS: Septal q waves were absent in 71 and present in 39 patients. The overall mortality rate was 47% (43 patients). The incidence of death was 49% (36 patients) in the group with no septal q waves and 18% (7 patients) in those who demonstrated septal q waves. On univariate analysis by Cox proportional hazard method, absence of septal q waves was found to be a strong marker of poor prognosis in CHF (P =.003, hazard ratio 1.40, 95% CI 1.10-1.67). Kaplan-Meier survival curves showed a significant difference in survival independent of age, New York Heart Association functional class, peak VO2, and QRS duration between these 2 groups. CONCLUSIONS: Absence of the normal septal q wave on 12-lead electrocardiography, which may indicate structural heart disease and myocardial fibrosis, is an independent predictor of poor prognosis in elderly patients with CHF.

Induced ischemia detected by dobutamine stress echocardiography in coronary heart disease patients after myocardial re-vascularization. Experience in a District General Hospital.

Most episodes of myocardial ischemia in patients with known coronary artery disease (CHD) are asymptomatic. Silent myocardial ischemia (SMI) is an important predictor of adverse outcome in patients with proven coronary artery disease. beta-blockers are effective in suppressing ischemia, and improve clinical outcome in patients with coronary artery disease. At present, it is common practice to stop treatment with beta-blockers in clinically asymptomatic patients after coronary artery bypass graft (CABG) and/or myocardial re-vascularization (PTCA/Stent), although the possible presence of SMI/inducible ischemia after myocardial re-vascularization is not known. We examined 56 asymptomatic CHD patients after coronary artery bypass graft (n=36), percutaneous coronary angioplasty PTCA/stent (n=15), or both (n=5); therapy with beta-blockers was stopped in all of them after myocardial revascularization. All these patients underwent a dobutamine stress echocardiography test (DSE test). The DSE test was proposed to these asymptomatic CHD patients to investigate the possible presence of SMI/inducible ischemia after myocardial re-vascularization. All patients had history of myocardial infarction or evidence of mildly impaired left ventricular function at rest as assessed by cardiac catheterization. Abnormal DSE studies occurred in eight of the 56 patients (14%; 95% C.I.: 6-26%). Therapeutic approaches specifically targeted at reducing total ischaemic burden include pharmacologic therapy and myocardial revascularization. On the basis of these data, it can be concluded that asymptomatic CHD patients after myocardial re-vascularization must be re-evaluated to rule out SMI/inducible ischemia that can be treated (e.g. with beta-blockers) reducing cardiovascular morbidity and mortality.

Electrocardiographic associations of right precordial Q waves help to distinguish anterior myocardial infarction from aortic stenosis.

Right precordial Q waves are ECG evidence of anterior myocardial infarction and can be present in patients with pathological left ventricular hypertrophy particularly caused by aortic stenosis. The aim of this study was to investigate the ECG features associated with Q waves in aortic stenosis and those in anterior myocardial infarction. We studied 16 patients with anterior myocardial infarction and 19 patients with aortic stenosis by means of ECG, echocardiography and clinical history. On the ECG, heart rate (70 +/- 20 beats/min vs. 83 +/- 20) and QT interval (380 +/- 65 ms vs. 390 +/- 50) did not differ between the two conditions. PR interval (160 +/- 15 ms vs. 185 +/- 30, P<0.05) and QRS duration (80 +/- 7.0 ms vs. 95 +/- 15, P<0.01) were both longer in patients with aortic stenosis than in those with myocardial infarction. The Q wave voltage in V1 (1.0 +/- 0.55 mV vs. 1.5 +/- 0.60) or V2 (1.3 +/- 0.5 mV vs. 1.8 +/- 0.85) and R wave voltage in V5 (0.7 +/- 0.7 mV vs. 2.1 +/- 0.9) or V6 (0.7 +/- 0.4 mV vs. 1.5 +/- 0.7, all P<0.01) were significantly less in patients with anterior myocardial infarction than in those with aortic stenosis. Q wave voltage over 1.3 mV in V1 or R wave voltage over 1.5 mV in V5 can differentiate aortic stenosis from anterior myocardial infarction with a sensitivity of 79% for each and specificities of 81 and 93.8%, respectively. Though the frontal QRS axis was similar in the two groups (28 +/- 45 degrees vs. 14 +/- 35, P>0.05), the horizontal QRS axis pointed laterally (-30 +/- 20 degrees) in aortic stenosis and posteriorly (-60 +/- 20 degrees, P<0.01) in anterior myocardial infarction. A horizontal QRS axis between zero and -45 degrees detected the presence of aortic stenosis with a sensitivity of 94.7% and a specificity of 81.3%. On echocardiography, left ventricular hypertrophy was found in most patients (94.7%) with aortic stenosis but not in those (0%) with anterior myocardial infarction. Left ventricular end diastolic dimensions (5.1 +/- 0.7 cm vs. 5.1 +/- 0.9, P>0.05) were similar in the two groups but the end systolic dimension was increased in patients with aortic stenosis (4.0 +/- 0.9 cm vs. 3.4 +/- 0.6, P<0.05). The systolic left ventricular function (shortening fraction: 23 +/- 8.0% vs. 34 +/- 7.0; Vcf: 0.8 +/- 0.26 circ/s vs. 1.3 +/- 0.26, both P<0.01) was significantly impaired in patients with aortic stenosis compared to those with myocardial infarction. In conclusion, in the presence of right precordial Q waves, the simple 12-lead ECG can provide important information on distinguishing anterior myocardial infarction from aortic stenosis. In particular, the QRS voltage in the chest leads and horizontal QRS axis can differentiate anterior myocardial infarction from aortic stenosis with high sensitivity and specificity.