The functional defect in amyloid heart disease. The "stiff heart" syndrome

Pericardial tamponade, a new complication of amyloid heart disease

With advancing age of the population and with echocardiographic means of diagnosis, amyloid disease of the heart is of increasing clinical interest. Advanced age, restrictive myocardiopathy, arrhythmias, and conduction disorders are familiar features of this disease. A 92 year old man with past history of hemiblock followed by complete heart block and transvenous pacemaker was admitted to the hospital because of increasing fatigue and the abrupt development of dyspnea. Examination revealed paradoxic pulse, markedly elevated central venous pressure, and echocardiographically demonstrated large pericardial effusion. Shortly after admission signs of tamponade developed; 1,000 ml of pericardial fluid was removed with prompt relief of dyspnea dna disappearance of paradoxic pulse and return of central venous pressure to normal. However, dyspnea soon recurred and subsequent hemodynamic measurements indicated increased right ventricular and left ventricular filling pressures. Echocardiography revealed no recurrent effusion or ventricular hypokinesis. Left ventricular ejection fraction by radionuclide ventriculogram was 64 percent. Echocardiography revealed ventricular wall thickening, normal chamber size, and glittering, sparkling myocardial echoes. On postmortem examination, there was extensive myocardial amyloidosis. There was no evidence of constrictive pericarditis or recurrent effusion. The unique aspect of this case was the combined presence of restrictive myocardiopathy and pericardial tamponade. To our knowledge, no previous case of tamponade due to amyloid heart disease had been reported.

Value of positive myocardial technetium-99m-pyrophosphate scintigraphy in the noninvasive diagnosis of cardiac amyloidosis

Ten consecutive patients with tissue-proven amyloidosis, seven of whom presented with congestive heart failure, were found to exhibit intense diffuse uptake of technetium-99m-pyrophosphate (Tc-99m-PYP) on cardiac radionuclide imaging. The patients exhibited echocardiographic and systolic time interval abnormalities suggesting combined restrictive and congestive cardiomyopathic changes. On M-mode echocardiograms, there was symmetrically increased thickness of the interventricular septum and left ventricular (LV) posterior wall in diastole (10 of 10), decreased fractional shortening of the LV minor axis diameter in systole (eight of nine), and decreased percent thickening of the LV minor axis diameter in systole (eight of nine) and LV posterior wall (10 of 10) in systole. Three patients demonstrated enlarged LV end-diastolic diameter. All 10 patients had abnormal PEP/LVET and eight had shortened LVETI. When combined with noninvasive tests of LV performance, positive myocardial pyrophosphate (PYP) scanning provides a new and useful adjunct in the diagnosis of amyloid heart disease.

Heart failure in outpatients: a randomized trial of digoxin versus placebo

The view that digitalis clinically benefits patients with heart failure and sinus rhythm lacks support from a well-controlled study. Using a randomized, double-blind, crossover protocol, we compared the effects of oral digoxin and placebo on the clinical courses of 25 outpatients without atrial fibrillation. According to a clinicoradiographic scoring system, the severity of heart failure was reduced by digoxin in 14 patients; in nine of these 14, improvement was confirmed by repeated trials (five patients) or right-heart catheterization (four patients). The other 11 patients had no detectable improvement from digoxin. Patients who responded to digoxin had more chronic and more severe heart failure, greater left ventricular dilation and ejection-fraction depression, and a third heart sound. Multivariate analysis showed that the third heart sound was the strongest correlate of the response to digoxin (P less than 0.0001). These data suggest that long-term digoxin therapy is clinically beneficial in patients with heart failure unaccompanied by atrial fibrillation whose failure persists despite diuretic treatment and who have a third heart sound.

Motion of pulmonic valve and constrictive pericarditis

Extreme respiratory variation in the depth of the "a" wave of the pulmonic valve echo was demonstrated in a patient with constrictive pericarditis; a mechanism for this finding is offered. Disparity in systolic and diastolic ventricular function in constriction is also useful in ruling out restrictive cardiomyopathy.

The echocardiographic assessment of cardiomyopathy: diagnosis, classification and problems

Two-hundred-and-sixty-three patients with cardiomyopathy were studied by M-mode echocardiography. Measurements of left ventricular cavity size, wall thickness and myocardial contraction were used to classify cardiomyopathy into "congestive" (212 patients) and "hypertrophic" (50 patients) groups; the "hypertrophic" group was further divided into asymmetric septal hypertrophy (37) and symmetric (concentric) mural thickening (13). Using clinical and electrocardiographic information as well as echocardiographic data, the latter group could then be further classified into "concentric infiltrative cardiomyopathy" (9) and "concentric hypertrophic cardiomyopathy" (4). The former either presented with signs of restriction or were known to have systemic amyloidosis; the electrocardiograph showed low voltage and myocardial contraction was impaired in advanced cases. The latter had evidence of severe left ventricular hypertrophy and resembled asymmetric septal hypertrophy clinically. Problems encountered with the echocardiographic diagnosis of congestive cardiography were mainly concerned with proper clinical interpretation of the echocardiographic data whilst technical difficulties in recording the echocardiogram and in interpretation of tracings were a common problem in hypertrophic cardiomyopathy.

Amyloid vascular disease: cord-like thickening of mucocutaneous arteries, intermittent claudication and angina in a case with underlying myelomatosis

A patient with established myelomatosis and an IgG paraproteinaemia presented with intermittent claudication. Indurated cord-like structures were noted on the dorsum of the right hand and the buccal surface of the lower lip, and biopsy of the hand lesion revealed massive amyloid deposition within the wall of an artery. Cord-like thickening of mucocutaneous arteries as a presenting sign of systemic amyloidosis in the absence of glossomegaly or other cutaneous lesions has not been reported previously. The presence of intermittent claudication and angina suggested that amyloid involvement of large arteries was extensively distributed.

Increased right ventricular wall thickness on echocardiography in amyloid infiltrative cardiomyopathy

In six patients with clinically significant amyloid infiltrative cardiomyopathy, echocardiographic right ventricular anterior wall thickness was significantly increased (mean 7.5 +/- 2.3 mm; range 5 to 10 mm). This finding in conjunction with the previously described abnormalities of the left ventricle (symmetric increase in wall thickness, diffuse hypokinesia, and small to normal left ventricular diastolic dimension) is consistent with the findings of a diffuse myocardial infiltrative process and should minimize confusion with constrictive pericarditis.

Ischemic heart disease secondary to amyloidosis of intramyocardial arteries

Among 108 patients with cardiac amyloidosis studied at autopsy between 1889 and 1977 there were 5 (4.6 percent) with severe occlusive amyloid deposits in intramyocardial arteries. The hearts of all five patients showed focal subendocardial ischemic injury, and the vessels supplying these areas had either complete or near complete luminal obliteration by amyloid. Clinically, four patients had congestive heart failure; one of these patients also had arrhythmias and one had angina pectoris. Neither the clinical nor the pathologic features of ischemic heart diseases could be attributed to disease of the epicardial coronary arteries. Amyloidosis of the intramyocardial arteries appears to be capable of producing localized areas of ischemic necrosis and may produce intractable congestive heart failure due to multiple areas of ischemic injury.

A case of sick sinus syndrome in primary systemic amyloidosis

A case of sick sinus syndrome due to primary systemic amyloidosis which involved mainly the heart and lungs is presented. The electrocardiogram showed various changes; low voltage, bradyarrhythmia with junctional escape beats, paroxysmal atrial tachyarrhythmia that terminates abruptly with subsequent long asystole, junctional rhythm from different origins and complete right bundle branch block which appeared at shorter and longer diastolic intervals. Histological examination showed an extensive amyloid infiltration in the upper parts of the conduction system, with major damage in the sinus node and also elsewhere in the heart. The patient died despite pacemaker implantation.

Evidence for cardiomyopathy in familial diabetes mellitus

Recent epidemiologic studies have suggested that cardiac disease in common in diabetics and may often have a noncoronary basis. To examine the status of the left ventricle, 17 adult-onset diabetics of familial type without hypertension or obesity underwent hemodynamic study and were compared to 9 controls of similar age. Of the 17, 12 subjects had no significant occlusive lesions by coronary angiography. From this group eight without heart failure had a modest, but significant, elevation of left ventricular end-diastolic pressure. End-diastolic and stroke volumes were reduced, but ejection fraction and mean rate of fiber shortening were within normal limits. The left ventricular end-diastolic pressure/volume ratio was significantly higher than controls. Afterload increments effected a significant increase of filling pressure compared to normals without a stroke volume response, consistent with a preclinical cardiomyopathy. Four patients with prior heart failure had similar but more extensive abnormalities. None had local dyskinesia by angiography, and lactate production was not observed during pacing-induced tachycardia. Left ventricular biopsy in two patients without ventricular decompensation showed interstitial collagen deposition with relatively normal muscle cells. These findings suggest a myopathic process without ischemia. Postmortem studies were performed in 11 uncomplicated diabetics. Nine were without significant obstructive disease of the proximal coronary arteries, and the majority succumbed with cardiac failure. On left ventricular sections, none had evident luminal narrowing of the intramural vessels. All nine exhibited periodic acid-Schiff-positive material in the interstitium. Collagen accumulation was present in perivascular loci, between myofibers, or as replacement fibrosis. Multiple samples of left ventricle and septum revealed enhanced triglyceride and cholesterol concentrations, as compared to controls. Thus, a diffuse extravascular abnormality may be a basis for cardiomyopathic features in diabetes.

Systolic and diastolic ventricular function in cardiac amyloidosis. Studies in six cases diagnosed with endomyocardial biopsy

Five cases of cardiac amyloidosis diagnosed after endomyocardial biopsy are described. Systolic function was normal in three cases as assessed by cardiac index, ejection fraction and maximal velocity of contractile element shortening at zero developed pressure. The diastolic dip and plateau wave form was a characteristic but not an invariable finding. Increased ventricular end-diastolic pressure but normal end-diastolic volume indexes in all cases implied a disorder of diastolic compliance. The diastolic pressure-volume plots suggested a sudden decrease in distensibility after normal early filling of the ventricle. The functional defect did not necessarily differ from that of other diseases of heart muscle. Therefore, hemodynamic data should not be relied upon for diagnostic purposes. Electron microscopy was the most reliable aid in making the diagnosis from the endomyocardial biopsy specimens especially in the presence of fibrosis. It may not be valid to assume a diagnosis of cardiac amyloidosis from the finding of amyloid in other organs.

Primary restrictive cardiomyopathy. Non-tropical endomyocardial fibrosis and hypereosinophilic heart disease

Eleven patients with a restrictive cardiomyopathy are described. Seven of these had biventricular disease and in them the haemodynamic abnormality resembled that in constrictive pericarditis but the condition was distinguishable because of unequal involvement of the two ventricles, murmurs of atrioventricular valve regurgitation, or characteristic ventricular deformity on angiography. Two of these patients had eosinophilia with the clinical features of Löffer's endocarditis. In 4 patients the disease was apparently confined to the left ventricle; they were investigated on account of atypical chest pain, third heart sound, or abnormal electrocardiogram. Simultaneous measurements of left ventricular pressure and volume throughout diastole were made in 3 patients and showed rapid but abruptly curtailed left ventricular filling. Transvenous endomyocardial biopsy in 2 patients showed fibrous tissue with collagen and irregular elastic fibrils. Surgical biopsy in 3 patients excluded pericardial constriction but was diagnostically unhelpful because of failure to obtain endocardium. Necropsy in one patient showed that the heart had features indistinguishable from tropical endomyocardial fibrosis. It is suggested that the spectrum of ventricular abnormalities in these patients results from endomyocardial fibrosis of varying severity and probably of differing cause. This study has shown that "tropical" endomyocardial fibrosis may occur outside the tropics and suggests that eosinophilia may play a leading role or associated part in the genesis of some cases.

The effects of tolbutamide on the myocardium in experimental diabetes

The effects of chronic tolbutamide treatment were examined in a diabetic animal model in which abnormal myocardial function and composition have previously been demonstrated. Eight diabetic dogs were given tolbutamide 250 mg/day orally and compared with seven untreated diabetics, five healthy dogs receiving tolbutamide, and eight normal controls. After one year, resting hemodynamic studies in the intact anesthetized state showed that treated diabetic dogs had a significantly higher left ventricular end-diastolic pressure of 12.1+/-1.3 mm Hg associated with normal end-diastolic volume, compared to 6.1+/-0.8 mm Hg in untreated diabetics (P less than 0.01) and 6.3+/-0.5 in normals. Stroke work and ejection fraction were similar to normals. Acute volume expansion revealed a larger rise of left ventricular end-diastolic pressure in treated and untreated diabetics than normals, without a significant stroke volume response in treated diabetics. Enhanced stiffness of myocardium appeared to be related to interstitial accumulation of periodic acid-Schiff staining material, further intensified in treated diabetics by triglyceride accumulation observed on electron microscopy and by chemical analysis. Thus treatment of diabetes with tolbutamide, despite improved glucose tolerance, effected further reduction of left ventricular function and altered morphology of myocardium.

Cardiac amyloidosis, contrictive pericarditis and restrictive cardiomyopathy

Cardiac amyloidosis is not characterized by a single hemodynamic pattern. Some of the cases present the clinical findings of restrictive cardiomyopathy and in these differentiation from constrictive pericarditis remains difficult in spite of the introduction of techniques designed to assess myocardial contractility and ventricular diastolic compliance. The clinical features and the demonstration of left ventricular diastolic pressure greater than right remain the most useful means of distinguishing restrictive cardiomyopathy from constrictive pericarditis. In other cases of cardiac amyloidosis the diastolic pressure is elevated throughout diastole and ventricular ejectile ability is lost. These cases do not simulate constrictive pericarditis and should not be classified as restrictive cardiomyopathy.