Hypertrophic obstructive cardiomyopathy and infective endocarditis: a report of seven cases and a review of the literature

Seven cases of infective endocarditis (IE) in patients with hypertrophic obstructive cardiomyopathy (HOCM) are presented in this report. The previous literature is critically reviewed, and the following points are discussed: (a) IE complicates HOCM in 5-9% of cases; (b) anatomical and haemodynamic alterations of HOCM cause microtraumas on heart valves and the endocardium; the resulting endocardial lesions represent sites for bacterial seeding as well as other congenital or acquired heart disease; (c) prognosis is worse in patients with IE associated with HOCM than in patients with IE alone or associated with congenital heart disease; (d) the most frequently isolated organisms are saprophytes; (e) most patients were exposed to bacteraemias before the onset of IE.

Relation of complex ventricular arrhythmias to presenting features and prognosis in dilated cardiomyopathy

To evaluate whether complex ventricular arrhythmias relate to presenting features and prognosis of dilated cardiomyopathy, 104 patients were studied from 1977 to 1987. At diagnosis, the 19 patients with complex ventricular arrhythmias (18%), as compared to the 85 patients without (82%), had a higher incidence of palpitation (P less than 0.01), severe dyspnea (P less than 0.001) and atrial fibrillation (P less than 0.01). They showed also higher mean right atrial pressures (10 +/- 5 vs 6 +/- 4 mm Hg, P less than 0.001) and higher right ventricular end-diastolic pressures (11 +/- 4 vs. 7 +/- 4 mm Hg, P less than 0.001) than patients without complex ventricular arrhythmias. Histologic samples were collected from the 32 patients (31%) studied since 1984 and semiquantitatively graded. The 11 patients with complex ventricular arrhythmias showed a higher frequency of severe interstitial fibrosis than the 21 patients without (64% vs. 24%, P less than 0.05), but they were otherwise similar as to the frequency of marked myocellular hypertrophy, changes of myocardial regression, endocardial fibrosis, attenuation of myocytes, hyperplasia of smooth muscle cells and infiltration by inflammatory cells. During a follow-up of 3.8 +/- 3.5 years, 35 patients (34%) died. Mortality was 58% (11 out of 19) in patients with complex ventricular arrhythmias and 28% (24 out of 85) in patients without (P less than 0.025). These results show that complex ventricular arrhythmias in dilated cardiomyopathy are associated with impairment of function of the right heart and severe interstitial fibrosis of the left ventricle, rather than with left ventricular dysfunction. Presence of complex ventricular arrhythmias also seems to identify those at high risk for death.

Acute effects of nifedipine versus isosorbide dinitrate on exercise tolerance in patients with isolated coronary artery occlusion and collaterals

The acute effects of slow-release nifedipine and isosorbide dinitrate on exercise tolerance were compared in nine patients with isolated total coronary artery occlusion showing retrograde filling via collaterals. All patients had a reproducible positive exercise stress test off medication before the study. Each patient was randomized to 10 mg slow-release nifedipine and 5 mg isosorbide dinitrate in a single-blind, cross-over study. The exercise stress test was performed 30 minutes after drug administration. After nifedipine, three patients had a negative exercise stress test, whereas the test was negative after isosorbide dinitrate only in one patient. A significantly higher exercise tolerance was detected at peak exercise after nifedipine than after isosorbide dinitrate, as shown by a longer exercise time (380 +/- 44 vs. 295 +/- 41 seconds, p less than 0.001), a more increased maximum work load (355 +/- 89 vs. 255 +/- 55 W x min, p less than 0.02), and a higher rate-pressure product (30,300 +/- 2,500 vs. 26,100 +/- 2,700, p less than 0.01). In conclusion, these results seem to suggest that nifedipine may have a vasomotor effect on collaterals, since it elevated the threshold of ischemia more than isosorbide dinitrate did in patients with isolated coronary artery occlusion, showing retrograde filling via collaterals.

Electrocardiographic findings in patients with hypertrophic cardiomyopathy. Relation to presenting features and prognosis

The relation of ECG findings to presenting features and prognosis was evaluated in 125 consecutive patients with hypertrophic cardiomyopathy (HC). Seventy-nine men and 46 women (mean age, 34 +/- 7 years) were studied since 1970. Most ECG features were similar in patients with and without a left ventricular outflow tract gradient. Those with obstruction had a higher prevalence of left ventricular hypertrophy according to ECG voltage criteria (54% vs. 28%, p less than 0.01), whereas higher grade ventricular arrhythmias were more common in patients without an outflow gradient (20% vs. 7%, p less than 0.05). The prevalence of ECG abnormalities was also similar in younger (less than or equal to 14 years) and older patients (greater than 14 years), and only repolarization abnormalities were more frequently detected in the older age group (56% vs. 32%, p less than 0.025). Stratification of patients according to the clinical state revealed that those who had moderate to severe functional limitation had a higher prevalence of atrial fibrillation than asymptomatic or mildly symptomatic patients (24% vs. 1%, p less than 0.001). There were no significant differences in most hemodynamic variables among patients dichotomized according to any specific ECG abnormality. Only patients with atrial fibrillation had significantly higher right ventricular end-diastolic pressure (10 +/- 7 vs. 6 +/- 4 mmHg, p less than 0.01), lower systolic index (22 +/- 8 vs. 37 +/- 15 ml/m2; beat, p less than 0.02) and lower ejection fraction (53 +/- 8 vs. 64 +/- 10%, p less than 0.001) than those in sinus rhythm.(ABSTRACT TRUNCATED AT 250 WORDS)

Different effects of epoprostenol on ischemia-induced ventricular arrhythmias in dogs

In 60 randomized dogs the effects of epoprostenol infusion (100 ng/kg/min) on ischemia-induced premature ventricular contractions (PVCs), ventricular tachycardia (VT), ventricular flutters and ventricular fibrillation were studied. The circumflex coronary artery occlusion canine model of sudden death was used. The results demonstrate different effects of epoprostenol on ischemia-induced ventricular arrhythmias: 1) both postischemic (7 of 30 vs 15 of 30, p = 0.0298) and postreperfusion (5 of 23 vs 8 of 15, p = 0.0492) ventricular fibrillations were prevented in epoprostenol dogs with an improvement of the global survival rate (18 of 30 vs 7 of 30, p = 0.0019) as compared to controls; 2) in epoprostenol treated dogs a significantly increased incidence of non lethal arrhythmias-including ventricular flutters that occurred in 12 of 30 dogs vs 4 of 30 in controls (p = 0.0195)--was observed; 3) a positive correlation between the percent diastolic pressure fall 10 min after the start of epoprostenol infusion and the number of non lethal arrhythmias was noted. However, hemodynamic effects of the compound, suggesting an oxygen sparing action, did not preclude the antifibrillatory effectiveness. Thus, the antifibrillatory and antiarrhythmic effects of epoprostenol after circumflex coronary artery occlusion and reperfusion in dogs seem independent from one another.

[Winging effect in interatrial defect after transseptal mitral valvuloplasty: an anatomical study]

In the balloon catheters the redundancy of the deflated balloon produces 2 or 3 sort of thin wings. The presence of wings can reduce the catheter "pushability" or, in certain conditions, can determine tissue lesion (winging effect). Simulating a transeptal valvuloplasty of the mitral valve by technique of the 2 balloon in human fresh heart, we studied the winging effect over the interatrial septum in 12 hearts; in the first 6 the atrial septum was dilated with a 6 mm balloon (Group A), in the second 6 the atrial septum was dilated with a 10 mm balloon (Group B). The procedure was completed introducing consecutively 2 bigger balloons (15 + 20 mm). We suppose that the winging effect of the 2 bigger balloons (15 + 20 mm) could counter balance the theoretical advantage of a small balloon (6 mm). The atrial septal defect (ASD) after septal dilatation was 5.0 +/- 0.59 mm x 1.56 +/- 0.25 mm (long axis x short axis) in Group A and 6.53 +/- 0.35 x 2.16 +/- 0.39 mm in Group B (p less than 0.01). The final ASD (after introducing the 2 bigger balloons) was 7.04 +/- 1.06 x 2.36 +/- 0.57 mm in Group A and 7.03 +/- 0.18 x 2.16 +/- 0.32 mm in Group B (NS). Our data show that the winging effect can determine biological negative effects.

Hypertrophic cardiomyopathy: is a left ventricular outflow tract gradient a major prognostic determinant?

The relationship of left ventricular outflow tract gradient as well as of clinical, ECG and haemodynamic data to presenting features and prognosis was evaluated in 125 consecutive patients with hypertropic cardiomyopathy, 79 men and 46 women (mean age: 34 +/- 7 years) studied between January 1970 and December 1985. Most clinical, ECG and haemodynamic findings were similar in the 44 patients (35%) with a pressure gradient (greater than or equal to 30 mmHg) and in the 81 patients (65%) without. Those with obstruction had greater ECG voltage SV1 and RV5; however, higher grade ventricular arrhythmias were more common in patients without obstruction. During a mean follow-up period of 7.6 +/- 4.5 years (range 2-18 years), death from a cardiac cause occurred in 28 patients (21 died suddenly) and was significantly less common in patients with a pressure gradient than in those without (11% vs 28%, P = 0.039). Univariate analysis of survival curves showed that the most powerful predictors of a poor prognosis were ejection fraction P = 0.0001), mean pulmonary artery pressure (P = 0.0001), dyspnoea (P = 0.001), left ventricular end-diastolic pressure (P = 0.002), complex ventricular arrhythmias (P = 0.029) and severe mitral regurgitation (P = 0.037). Using multivariate analysis, a decreased ejection fraction (P = 0.006) and a raised mean pulmonary artery pressure (P = 0.022) were the only independent prognostic determinants. Thus, the presence of a left ventricular outflow tract gradient does not seem of adverse prognostic significance. Risk factor characterization in patients with hypertrophic cardiomyopathy may be improved by assessment of ventricular arrhythmias in the context of left ventricular function.

[Improvement in the accuracy of diagnosis of ischemic heart disease with simultaneous radioisotope evaluation of regional myocardial function perfusion and an exercise test]

The recently developed myocardial agent methoxy-isobutyl-isonitrile (MIBI), labelled to 99mTc, allows one to evaluate global and regional ventricular function as well as myocardial perfusion by means of a single exercise stress test, significantly increasing diagnostic accuracy for coronary artery disease. Between September 1988 and March 1989, 407 patients with either suspected or already ascertained coronary artery disease underwent simultaneous assessment of regional ventricular function with first pass radionuclide angiography, and of myocardial perfusion with single photon emission computerized tomography, by means of 2 injections of 99mTc-MIBI at rest and at peak of the same exercise test. Out of these patients, 56 (52 men and 4 women, whose mean age was 57 +/- 7 years) underwent coronary angiography within 6 months of radionuclide examination and were included in the study. There were 13 1-vessel, 26 2-vessel and 17 3-vessel disease patients. Thirty-six of them had had a previous (greater than 6 months old) myocardial infarction, on the anterior wall in 16 patients, on the inferior wall in 20. In all patients a computerized bicycle stress test was performed; interruption criteria were ST segment depression greater than or equal to 1 mm in 27 patients (48%), the achievement of a heart rate greater than 85% of maximal age-predicted heart rate in 12 patients (22%) and fatigue in 17 patients (30%). Scintigraphic results were compared to angiographic findings: global sensitivity and specificity of the simultaneous evaluation were 82% and 81%, respectively, vs 95% and 56% of functional results and 85% and 71% of perfusion results, respectively. Regional analysis was also performed, by dividing scintigraphic images into the territories supplied by the 3 main coronary vessels, i.e., left anterior descending artery (LAD), left circumflex artery (LCx) and posterior descending artery (PD). On LAD territory the simultaneous evaluation achieved a sensitivity of 88% and a specificity of 63%, vs 98% and 38% of functional analysis and 88% and 50% of perfusional analysis, respectively. On LCx territory sensitivity and specificity were respectively 71% and 96%, vs 91% and 64% of function, and 77% and 96% of perfusion alone. On PD territory sensitivity was 85%, vs 94% and 91%, respectively; specificity was 73%, vs 55% and 55%, respectively. Combined functional and perfusional analysis achieved a 68% sensitivity in identifying less than or equal to 75% coronary narrowings, and a 90% sensitivity for greater than 90% narrowings.(ABSTRACT TRUNCATED AT 400 WORDS)

Long-term prognosis in children with hypertrophic cardiomyopathy: an analysis of 37 patients aged less than or equal to 14 years at diagnosis

The relation of clinical, electrocardiographic, and hemodynamic findings at diagnosis to presenting features and prognosis of hypertrophic cardiomyopathy in childhood was evaluated in 37 consecutive patients below 14 years of age at time of diagnosis (24 males and 13 females, mean age 7 +/- 4 years). A left ventricular out-flow tract gradient (mean 42 +/- 27 mmHg) was detected at cardiac catheterization in 13 (35%) patients. Clinical, electrocardiographic, and hemodynamic features in patients with and without a pressure gradient were similar. Patients who had moderate to severe functional limitation had a higher incidence of syncopal episodes (p less than 0.001), lower ejection fraction (p less than 0.01), raised pulmonary artery pressure (p less than 0.001), and left ventricular end-diastolic pressure (p less than 0.01). During a follow-up of 9.2 +/- 5.1 years (range 2-18), 9 (24%) patients died suddenly (2 with a recorded left ventricular outflow tract gradient). Univariate analysis showed that reduced ejection fraction (p = 0.0001), syncopal episodes (p = 0.003), increased left ventricular end-diastolic pressure (p = 0.03), and severe dyspnea (p = 0.04) were associated with a poor prognosis. However, multivariate analysis revealed ejection fraction (p = 0.0001) and syncopal episodes (p = 0.0097) as independent predictors of survival. In conclusion, sudden cardiac death was common and was well predicted by the combination of left ventricular dysfunction and syncope at time of diagnosis.

[Fulguration of the bundle of His. Description of 3 new cases]

With the purpose to call attention to the clinical utility of fulguration of the His bundle (a therapeutic procedure somewhat neglected in Italy) 3 new cases are presented. All patients had a long history of supraventricular tachyarrhythmias refractory to conventional treatment. Patients 1 and 2, in whom surgical correction of tetralogy of Fallot and mitral valve replacement, respectively, had been performed several years before, had chronic atrial tachycardia with congestive heart failure. Patient 3 suffered from persistent atrial flutter, in the absence of demonstrable organic heart disease. Three shocks of 320 J were necessary to induce complete AV block in patient 1 and 2. In patient 3, a single discharge (320 J) resulted in interruption of AV conduction. Twenty-four hours after the procedure, a rate-responsive ventricular pacemaker was implanted in all patients. The success of the procedure was confirmed 3 months later, during transitory pacemaker inhibition. Patients 1 and 3 exhibited atrial tachycardia and atrial flutter, respectively, but complete AV block was still present, with junctional escape rhythm at a rate of 40 and 45 b/min; in patient 2 atrial tachycardia with high degree AV block, and a mean ventricular rate of 75 b/min, were observed. Refinement of transcatheter ablative techniques is desirable. However, even in the present status, catheter ablation of the His bundle is an effective, low-risk procedure for patients with refractory supraventricular tachyarrhythmias.

Quantitation of renal blood flow by contrast ultrasonography: preliminary results

Contrast ultrasonography, employing tracers behaving like red blood cells, is a promising technique to study regional blood flow distribution. Aim of this note is to quantitate renal blood flow in the dog using contrast ultrasonography. Mathematical formulae derived from the classical dye-dilution theory are applied. Ten different renal blood flow levels (ranging from 16 to 125 ml/min) were obtained by means of mechanical (stenosis and reperfusion) and pharmacological interventions (iv infusion of adrenaline, noradrenaline and fenoldopam). Renal blood flow was measured by electromagnetic flow-meter and contemporary calculated by contrast ultrasonography. The correlation coefficient between measured and calculated flow was 0.92 (p less than 0.01). Contrast ultrasonography is a technique capable of measuring renal blood flow at a wide range of different flow levels.

The role of indium-111 antimyosin (Fab) imaging as a noninvasive surveillance method of human heart transplant rejection

The identification of rejection after heart transplantation in patients receiving cyclosporine immunosuppressive therapy requires the endomyocardial biopsy, an invasive method associated with a finite morbidity. To evaluate the role of indium-111 antimyosin (Fab) scintigraphy as a noninvasive surveillance method of heart transplant rejection, the Fab fragment of murine monoclonal antimyosin antibodies labeled with indium-111 was administered intravenously in 30 scintigraphic studies to 10 consecutive heart transplant recipients. Endomyocardial biopsy specimens were obtained 72 hours after each scintigraphic study. Nineteen scintigraphic studies had negative findings; no false negative finding was obtained. Eleven antimyosin scintigraphic studies had positive findings, and in these studies endomyocardial biopsy revealed mild rejection in two cases, moderate acute rejection with myocyte necrosis in two cases, myocyte necrosis as a consequence of ischemic injury in six cases, and possibly cytotoxic damage in one case. Antimyosin scintigraphy may represent a reliable screening method for the surveillance of heart transplant patients. In the presence of a negative finding from antimyosin scintigraphy, it may be possible to avoid endomyocardial biopsy. Conversely, in patients who have a positive finding from antimyosin scintigraphy, the endomyocardial biopsy is mandatory to establish the definitive diagnosis by histologic examination of the myocardium.

[Asymptomatic pre-excitation. Identification of potential risk using transesophageal pacing]

Noninvasive assessment of the conducting capability of the accessory pathway (AP) in asymptomatic patients with a preexcitation ECG pattern is desirable, since life-threatening arrhythmias and sudden death may be the first manifestation of the Wolff-Parkinson-White (WPW) syndrome. To investigate whether in patients with preexcitation ECG pattern the absence of clinical arrhythmias excludes the potential for rapid ventricular responses, transesophageal atrial pacing (TAP) was performed in 11 subjects (9 male, 2 female), aged 5 to 43 years. The extrastimulus technique was used in order to define the refractory periods and in the attempt to induce reciprocating tachycardia. Incremental TAP up to the occurrence of block in the AP was instituted, and attempts to induce atrial fibrillation (AF) with rapid burst pacing were made. One to one atrioventricular conduction over the AP at progressively increased cycle lengths (CLs), and the shortest R-R interval between pre-excited beats during induced AF were evaluated. The following findings were considered predictors of potential life-threatening arrhythmias: 1) anterograde refractory period of the AP equal to or shorter than 250 ms; 2) one to one AP conduction at CLs shorter than 300 ms; 3) shortest R-R interval, during induced AF, less than 250 ms. Sustained reciprocating tachycardia could not be induced in all patients in spite of the use of the use of an aggressive stimulation protocol. The anterograde refractory period of the AP could not be defined in 9 patients. In the remaining 2 this parameter was longer than 250 ms. In 8 patients (72%), the shortest CL maintaining 1:1 AP conduction ranged from 220 to 280 ms (mean 253 +/- 19).(ABSTRACT TRUNCATED AT 250 WORDS)

A possible role of chromatin and tightly-bound chromatin proteins on enzyme-catalyzed methylation of DNA

Upon extensive digestion with DNAaseI of placenta chromatin matrix, previously "stripped" from its loosely-bound components by high-salt extraction, a fraction is obtained that contains almost no endogenous DNA methylase activity but whose DNA, if still included in this whole fraction--not if it has been purified to a protein-free condition--is a good substrate for externally added enzyme. This chromatin matrix can even cause a significant stimulation of methylation of single-stranded Micrococcus luteus DNA by placental methylase. In vivo, this phenomenon may have possible counterparts in the existence of highly-methylated regions of chromatin loops that appear to be protected by tightly-bound protein components from digestion of the "stripped loops" with DNAaseI.

[Electrophysiologic significance of the electric alternans in supraventricular tachycardia]

To investigate the electrophysiologic significance of QRS alternans during narrow QRS tachycardia, transesophageal atrial pacing and recording was performed in 24 patients with a history of paroxysmal supraventricular tachycardia. Standard electrocardiograms (ECG) showed ventricular preexcitation in 15 patients and normal QRS pattern in 9. The ventriculo-atrial interval during tachycardia, as defined by means of transesophageal electrogram, allowed tentative diagnosis of the tachycardia mechanism. A 12-lead ECG was recorded either during spontaneous or induced tachycardia, as well as during transesophageal atrial pacing at increasing rates. Electrical alternans occurred spontaneously in 8 patients (33%, Group A): 5 with accessory pathway reentry (mean VA: 136 +/- 43 ms), 3 with intranodal reentry (mean VA: 48.3 +/- 43 ms). Tachycardia rate ranged between 170 and 230 b/min (mean 200.7 +/- 16). In 2 patients alternation of the QRS occurred only in the presence of a heart rate exceeding 180 and 190 b/min, respectively. The amplitude of QRS remained stable during tachycardia in 16 patients (67%, Group B): 14 with accessory pathway reentry (mean VA: 137.5 +/- 32 ms), 2 with intranodal reentry (mean VA: 45 +/- 7 ms). In this group, the tachycardia rate ranged from 150 to 210 b/min (mean 175 +/- 12). Incremental transesophageal atrial pacing up to rates equal to that of tachycardia was performed in 5 patients of Group A and in 8 of Group B. Electrical alternans could not be induced in both groups with pacing at progressively increasing rates. In contrast, the phenomenon was elicited in 2 patients of Group A when an abrupt pacing at the same rate that had showed the spontaneous occurrence of QRS alternans was instituted.(ABSTRACT TRUNCATED AT 250 WORDS)

Determinants of end-stage idiopathic dilated cardiomyopathy: a multivariate analysis of 104 patients

Our purpose in this study was to investigate the correlation of clinical, electrocardiographic, hemodynamic, and histopathologic features at diagnosis with the long-term prognosis in 104 patients with idiopathic dilated cardiomyopathy to determine which factors are the independent determinants of the end-stage disease. During a mean follow-up of 3.8 +/- 3.5 years, 35 patients (33%) died, 14 (13%) suddenly and 21 (20%) from congestive heart failure. Univariate analysis of survival curves disclosed that clinical and electrocardiographic variables at diagnosis were similar in survivors and non-survivors. On the contrary, patients who subsequently died had higher mean right atrial pressure (p = 0.0001), right ventricular end-diastolic pressure (p = 0.0061), mean pulmonary artery pressure (p = 0.0001), and left ventricular systolic (p = 0.0049) and end-diastolic (p = 0.0021) pressure than survivors. They also exhibited larger left ventricular end-diastolic (p = 0.0046) and end-systolic (p = 0.0027) volumes, lower ejection fraction (p = 0.0001), and a greater proportion had severe mitral regurgitation (p = 0.0095). Univariate analysis of histologic findings collected in a subgroup of patients referred since 1984 revealed a mild degree of myocellular hypertrophy to be associated with a poor prognosis (p = 0.0217). Multivariate analysis selected only mean right atrial pressure (p = 0.0022), ejection fraction (p = 0.0089), and end-systolic volume (p = 0.0265) as independent determinants of cardiac death. Our results suggest that cardiac catheterization is mandatory for risk stratification of patients with idiopathic dilated cardiomyopathy, since it allows the assessment of hemodynamic, angiographic, and histopathologic features helpful in identifying patients with a poor prognosis.

[Validity of some electrocardiographic criteria in left ventricular hypertrophy]

The aim of the study was the assessment of the sensitivity, specificity and accuracy of some ECG criteria of left ventricular hypertrophy (LVH). Left ventricular mass (LVM) measured on the M-mode echogram of the left ventricle was the reference standard. Ninety-four (94) unselected, consecutive clinical patients (34 women, 60 men, average age 47 years) underwent in the same day, ECG and echocardiogram. Exclusion criteria were the presence of ischemic heart disease, atrial fibrillation and Wolff-Parkinson-White syndrome. The ECG tracings were interpreted independently by 2 investigators following 5 independent criteria of LVH: 1) Sokolow-Lyon voltage criterion (SL); 2) a modified Romhilt-Estes point score (REM); 3) left atrial abnormality (LAA); 4) left ventricular strain; 5) a new voltage criterion RaVL + SV3 corrected by sex and age. The left ventricular M-mode echograms were recorded using a left parasternal approach and were interpreted independently by 2 investigators. LVM was measured using the "Penn convention" and taking the R wave peak as end-diastole. The prevalence of LVH (= LVM 215 g) in the study population was 47%. The following results were achieved (sensitivity, specificity, accuracy): SL: 68.2%, 84%, 76.6%; REM: 63.6%, 90%, 77.7%: LAA: 36.4%, 84%, 61.7%; strain 52.3%, 72%, 62.8%; RaVL + SV3: 54.5%, 82%, 69.1%. Our data suggest: 1) the high sensitivity, specificity and accuracy of Romhilt-Estes point score are confirmed; 2) the sensitivity of Sokolow-Lyon voltage criterion is reevaluated; 3) the most sensitive morphological criterion seems to be the left ventricular strain; 4) a new voltage criterion could be useful.

Angulated transverse tomographic sections to measure cardiac dimensions by magnetic resonance imaging: a comparison with 2D-echocardiography

Magnetic resonance imaging (MRI) has shown low accuracy in measuring cardiac dimensions in normal subjects, when transverse tomographic sections are used in comparison with 2D-echocardiography. The rationale of this study was to compare cardiac dimensions in 19 volunteers based on angulated (30 degrees caudo-cranial) transverse tomographic sections both in MRI and 2D-echo. Since the planes investigated by both techniques are superimposable, highly significant correlated Ao, LA, IVS, LW, LV, and RV dimensions are observed. Standardized MRI tomography permits reduction of total examination time and assures repeatability. Thus, using the method reported here, cardiac dimensions in humans might be obtained accurately by MRI.