Effects of adrenaline on ventricular function and coronary haemodynamics in relation to catecholamine handling in transplanted human hearts

We investigated cardiovascular and coronary responses to intravenous infusions of adrenaline, which raised arterial concentrations in a stepwise fashion from basal to about 5-6 nmol.l-1, in 11 non-rejecting heart transplanted patients, and in eight intact innervated subjects. Cardiac adrenaline extraction and noradrenaline release rate were also measured. The transplanted patients showed larger increases in heart rate (36 +/- 11% vs 16 +/- 6%, P < 0.0001) and cardiac index (80 +/- 30% vs 56 +/- 19%, P < 0.05), while stroke volume increments were similar in the two groups (32 +/- 17% vs 35 +/- 13%). The study groups did not differ with respect to changes in arterial pressure, cardiac work or peripheral resistances. Coronary sinus blood flow increased to a greater extent in the transplanted group (75 +/- 35% vs 48 +/- 31%, P < 0.05) and myocardial oxygen consumption also tended to increase more in these patients (78 +/- 42% vs 48 +/- 34%, NS). Myocardial adrenaline extraction was greatly reduced in the transplant patients (-6 +/- 25% vs 64 +/- 18%, P < 0.001), while forearm adrenaline extraction was similar in the two groups (41 +/- 22% vs 40 +/- 23%, NS). Cardiac noradrenaline overflow tended to be lower in the transplanted group (12 +/- 62 vs 48 +/- 43 pmol.min-1, NS). There was a wide range of noradrenaline overflow values (-64 to 147 pmol.min-1) and definite high values in three patients. Cardiac noradrenaline overflow was not correlated to heart rate responsiveness to adrenaline. We conclude that patients with cardiac transplantation respond to adrenaline with exaggerated increases in heart rate and thus in cardiac output. High values of cardiac noradrenaline overflow are seen in some transplant recipients and may suggest reinnervation. Signs of reinnervation are not associated with consistently lower heart rate responses to beta-adrenergic stimulation.

Development of myocardial beta-adrenergic receptor density and adenylate cyclase activity after human heart transplantation

An increase in basal heart rate caused by a lack of vagal control and chronotropic supersensitivity to epinephrine has been shown in transplanted human hearts. Prejunctional and/or postjunctional origins for this supersensitivity have been suggested, the latter involving changes in the number of myocardial beta-adrenergic receptors or in the receptor adenylate cyclase system. To directly determine the time course of change, serial determinations were performed during the first 3 months after heart transplantation. The beta-adrenergic receptor density measured by iodine 125-labelled iodocyanopindolol binding in 61 endomyocardial biopsy specimens (a mean of 6.1 +/- 0.58 biopsies from each of 10 patients) showed great intraindividual and interindividual variability (56.6 +/- 6.8 fmol/mg protein) with no mean trend toward gradually changing receptor densities. Isoproterenol-stimulated adenylate cyclase activity measured in 33 biopsy specimens (a mean of 5.5 +/- 0.67 biopsy specimens from each of six patients) varied considerably (112.5 +/- 13.8 pmol cyclic adenosine monophosphate/mg protein/min), again with no definite tendency with regard to the development over time. The beta-adrenergic receptor densities showed no statistical correlation with the degree of rejection as assessed by histologic criteria and antimyosin ration. These results suggest that in the first 3 months after heart transplantation beta-adrenergic receptor density and adenylate cyclase responses to 10 mumol/L isoproterenol do not change and that beta-adrenergic receptor density in the transplanted myocardium does not seem to be affected by the degree of rejection.

Two-year follow-up after laser thermal balloon angioplasty (LTBA) in lower extremities: initial experience

We describe the results obtained with the use of laser thermal balloon angioplasty (LTBA) in the treatment of atherosclerosis obliterans of the lower limbs in 37 patients (34 males, 3 females, mean age 58 +/- 9 years) with occlusive arterial disease (Fontaine stages II-IV) presenting 39 significant lesions. Immediate results and two years of clinical follow-up are analyzed. Initial ankle/brachial Doppler index was 0.51 +/- 0.17. Eighteen lesions were located in the iliac area (13 stenoses 2.3 +/- 1 cm and 5 occlusions 4.2 +/- 3 cm) and 21 lesions in the femoropopliteal area (5 stenoses 2.6 +/- 2 cm and 16 occlusions 5.7 +/- 3 cm). A percutaneous procedure was used in 38 cases. In only one case was femoral dissection needed. The laser source was argon in 26 cases and Nd-YAG in 13. Initial success was 85% (89% in iliac lesions and 81% in femoropopliteal lesions; 100% in stenoses and 70% in occlusions). The presence of occlusion (p less than 0.01) and/or calcium (p less than 0.05) negatively influenced the immediate results. No major complications were observed; seven (17%) minor complications occurred. Ankle/brachial Doppler index after treatment was 0.82 +/- 0.21. Cumulative clinical patency for successfully treated patients after two-year follow-up was 91%. LTBA thus represents an effective and less aggressive way of treating peripheral atherosclerosis obliterans. In spite of some limitations, it is useful in selected patients. The results of this study are very much like those in the literature for similar series and early experience.

Antiplatelet agents and their effect on complications during or soon after percutaneous transluminal coronary angioplasty

In a retrospective study, during which 179 patients had undergone percutaneous transluminal coronary angioplasty (PTCA), the overall initial success rate fell suddenly and unexpectedly from more than 90% to 70.4%: 54.9% in patients not receiving antiplatelet therapy and 86.4% in patients treated orally with 300 mg triflusal three times daily or 300 mg acetylsalicylic acid plus 75 mg dipyridamole three times daily. The initial success rate was similar in patients with unstable (66.0%) and stable (77.6%) angina. The overall incidence of severe complications (mainly occlusion) was 16.2% and was significantly (P less than 0.01) greater in the patients not receiving antiplatelet therapy (23.1% versus 9.1%). There was no significant difference between incidence according to antiplatelet therapy used. It is concluded that antiplatelet therapy during the peri-angioplasty period (from 2 days before to 2 days after) may prevent periprocedural events in patients undergoing PTCA.

Left ventricular dynamics and plasma catecholamines during isometric exercise in patients following cardiac transplantation

Haemodynamics and plasma catecholamine responses to isometric exercise were evaluated invasively in 11 orthotopic heart transplant recipients and seven control subjects. Differences in haemodynamic responses between the two groups were already apparent after one min of handgrip at 30% of maximal voluntary contraction, and very pronounced at the end of the fourth minute. At this point transplanted patients showed smaller increments in heart rate (4.8 +/- 3.2 vs 20.4 +/- 14.1 beats.min-1, P less than 0.001), mean arterial pressure (13.7 +/- 7.2 vs 31.5 +/- 12.2 mmHg, P less than 0.001) and cardiac index (0.51 +/- 0.22 vs 1.02 +/- 0.53 L.min-1.m-2, P less than 0.01), whereas left ventricular end-diastolic pressure increased to a greater extent (8.8 +/- 4.9 vs 2.2 +/- 1.8 mmHg, P less than 0.01). Stroke volume index increased similarly (3.8 +/- 1.8 vs 2.0 +/- 3.5 ml beat-1.m-2, NS) and systemic vascular resistance remained unchanged in both groups. The slopes of the left ventricular function curves (ratio of change in left ventricular work to change in left ventricular end-diastolic pressure) indicated depressed left ventricular function in the transplanted patients. The two groups showed similar increments in mixed venous plasma norepinephrine and epinephrine indicating normal sympathoadrenal activation in the transplanted patients. In conclusion, transplanted hearts respond to handgrip with attenuated increases in heart rate, cardiac output and arterial pressure and by increasing left ventricular filling pressure, suggesting a poor contractile reserve probably due to denervation. Circulating catecholamines, especially epinephrine, probably contribute to the cardiac responses to isometric exercise.

[Coronary fistula to the right ventricle in heart transplant patients as a complication of repeated endomyocardial biopsies]

Ninety-six coronary angiographies of 30 orthotopic heart transplant recipients were studied. Eleven coronary artery fistulas to right ventricle were seen in 7 (23.3%) patients; five involved the left anterior descending artery, four the right coronary artery, and two the circumflex artery. All the coronary arterial fistulas appeared within the first year after transplantation, when endomyocardial biopsies were more frequent. In the review of the histologic samples, we found coronary arterioles greater than 0.15 mm of diameter in 3 of 7 patients with coronary arterial fistula; on the contrary, those were not found in any of the 69 histologic samples of 23 heart transplant patients without coronary fistula (p less than 0.001). Neither clinic nor hemodynamic abnormalities were seen in any patient during the follow-up. The coronary fistula had a benign course, with a tendency to decrease in size and to close spontaneously.

Five years of angiographic and clinical follow-up after successful percutaneous transluminal coronary angioplasty

The first 67 consecutive patients (77 lesions) who underwent successful coronary angioplasty (PTCA) at our hospital were clinically followed with serial exercise testing over a 5-year (4 to 7) observation period. Two sequential angiographic controls were performed 6.9 +/- 4.6 (64 patients) and 49.5 +/- 21.6 (42 patients) months after PTCA. The 5-year risk of cardiac death was 8%, of myocardial infarction 2%, or coronary artery bypass grafting 16% and of repeat PTCA 8%. At 5 years, 67% of the patients remain asymptomatic. Restenosis greater than or equal to 70% diameter was observed within the first year after PTCA in 30% of the patients. Progression of coronary artery disease (CAD) was observed in 13 patients (20%). In the first angiographic control, CAD progression was 4% (3/77) in dilated and 3% (3/115) in non-dilated arteries (ns). In the second angiographic control, it was 7% (3/45) and 10% (8/81), respectively (ns). Thus good clinical and angiographic results are still observed after 5 years. Restenosis is an early, self-limited, time-restricted phenomenon that occurs in 30% of patients. Angioplasty does not appear to accelerate CAD progression.

Reversal of rejection-induced coronary vasculitis detected early after heart transplantation with increased immunosuppression

Four patients who underwent heart transplantation, in whom coronary obstruction was seen early after transplantation, are described. Repeated acute rejection episodes were detected within the first 2 months in each patient. Coronary obstruction or ischemia was shown through a combination of T1-201 isotopic study findings, evidence of vasculitis of a small coronary arteriole seen at endomyocardial biopsy, or coronary angiographic results. Vigorous treatment for rejection (antithymocyte globulin and bolus methylprednisolone) was given, and coronary artery lesions or myocardial ischemia resolved after treatment. Rejection-induced coronary obstruction should be considered in patients with repeated acute rejection episodes who are predisposed to the development of vascular rejection. Early after transplantation such obstruction is caused by diffuse vasculitis of small and medium-sized vessels and may be reversed with increased immunosuppression.

Prevention of aortocoronary vein-graft attrition with low-dose aspirin and triflusal, both associated with dipyridamole: a randomized, double-blind, placebo-controlled trial

A randomized, double-blind, placebo-controlled trial was performed in 209 patients to evaluate the efficacy of a low dose of aspirin plus dipyridamole or that of a new antiplatelet agent (triflusal) plus dipyridamole in the prevention of aortocoronary vein-graft occlusion. An angiographic control performed in 161 patients 9 days after surgery showed no significant differences between groups, but a new control on 138 of those patients 6 months later did show significant linear trends towards fewer distal anastomosis occlusions (P = 0.027) from the placebo (24%, 22/91) to the aspirin (16%, 17/106) and to the trifusal groups (12%, 10/86), and towards fewer new occlusions (P = 0.056) from 12% (9/78) to 10% (10/99) and to 2.6% (2/78), respectively, in the same groups. A multivariate logistic regression model, used to determine the effect of 33 variables on distal anastomosis occlusion at 6 months control, demonstrated that diameter of distal bed (P = 0.006), moderately to severely atherosclerotic distal bed (P = 0.003) and the interactions between poor distal bed and triflusal (P = 0.005) were independent predictors of occlusion. Thus, triflusal plus dipyridamole appeared superior to low-dose aspirin plus dipyridamole in the prevention of vein-graft occlusion, independently of coronary and vein-graft determinants of occlusion.

Clinical and hemodynamic results of cardiac valve replacement with the Monostrut Björk-Shiley prosthesis

Between May 1983 and April 1986, 318 patients underwent cardiac valve replacement with the Monostrut Björk-Shiley prosthesis. There were 136 aortic valve replacements, 128 mitral valve replacements, and 54 multiple replacements. A total of 373 valves were implanted. Associated procedures were done in 79 (25%) of the patients. Hospital (30-day) mortality rate was 5.6% (18 patients): 2.9% (n = 4) after aortic, 7.8% (n = 10) after mitrals and 7.4% (n = 4) after multiple valve replacement. Follow-up was obtained in all 300 operative survivors, for a total of 500 patient-years (mean 18 months). Actuarial survival rate, excluding operative deaths, at 4 years was 94.7% +/- 1.5% (mean +/- standard error of the mean). There were 16 thromboembolic episodes (3.2/100 patient-years). Freedom from all valve-related complications was 87% +/- 2.4% at 3 1/2 years. Neither valve thrombosis nor structural failure has been observed. Eighty percent of the patients are in New York Heart Association functional class I. Forty-two patients (26 with aortic and 16 with mitral valve replacement) underwent cardiac catheterization a mean of 6 1/2 months after the operation. In the aortic position, peak gradients were an average of 6.9 +/- 1.2 mm Hg. Mean systolic gradients were 12.4 +/- 6.3 mm Hg and did not increase with exercise. In the mitral position, end-diastolic gradients were an average of 2.1 +/- 2 mm Hg and mean gradients, 5.9 +/- 2 mm Hg. Discharge coefficient (estimated orifice area/geometric area) was 0.63 +/- 0.2 for the aortic and 0.53 +/- 0.2 for the mitral prostheses. Disc opening was maximal in most patients. These results indicate that the Monostrut prosthesis has a low rate of thromboembolic events, no structural failures or thrombotic obstructions and excellent hemodynamic performance, especially in the small aortic sizes (discharge coefficient for 19 and 21 mm valves, 0.77).

Endomyocardial diagnosis of cardiac lipomatosis

A patient with severe isolated right-sided cardiac failure of unknown origin is presented in whom three right ventricular endomyocardial biopsies obtained in different bioptome positions disclosed a yellowish material which was confirmed at histological examination as fat. At operation, a complete replacement of atrial and ventricular myocardium by fat was noted. this previously unreported use of endomyocardial biopsy is emphasized, especially when the differential diagnosis of isolated right-sided heart failure is considered.

Haemodynamic effects of molsidomine in patients with severe chronic coronary disease

The haemodynamic effects of a single dose of intravenous molsidomine were assessed in 12 patients with severe coronary disease. The investigation was carried out at rest during angina induced by pacing and after molsidomine during pacing at the rate at which angina had been produced. During angina, left ventricular systolic and end-diastolic pressure rose, left ventricular stroke work fell and coronary flow and myocardial oxygen consumption increased by 58.3% above the control levels. After the administration of molsidomine, atrial stimulation was not followed by angina and there were no significant changes in systolic blood pressure. Left ventricular end-diastolic pressure fell sharply and coronary flow and myocardial oxygen consumption were only 38% and 33% higher, respectively, than the control levels. The beneficial effects of molsidomine in ischaemic heart disease, therefore, are the result of peripheral vasodilation which, by reducing the preload and afterload, lowers the oxygen requirements of the myocardium and thus increase the threshold for angina. A direct action on the coronary network can not be excluded but if such an action does exist it must be very small in the light of the marked systemic effect.

Hemodynamic evaluation of the integral monostrut Björk-Shiley prosthesis in the aortic position

Between May, 1983, and November, 1984, the new integral monostrut Björk-Shiley prosthesis was used for aortic valve replacement in 62 patients. The prosthesis is machined from a solid piece of cobalt alloy and has no welded joints. The traditional U-shaped outlet strut has been replaced by a projecting metal finger that holds the disc in place. The disc opens to 70 degrees and is convexoconcave. Successful transseptal heart catheterization was performed in 23 patients an average of 6 months following operation to evaluate the hemodynamic performance of the prosthesis. The mean peak-to-peak gradient was 7.73 +/- 7.49 mm Hg (+/- standard deviation). In five valves it was 0, and in only three was it higher than 15 mm Hg. Significant peak gradients were directly related to the valve index (valve area/body surface area). Mean systolic gradient at rest was 12.7 +/- 6.27 mm Hg and did not increase after exercise. Effective orifice areas were adequate, and the discharge coefficient ranged from 0.77 for the 21-mm prosthesis to 0.48 for the 29-mm prosthesis. Minimal regurgitation, which was washed out on the next systole, was observed with all sizes of the prosthesis. Disc opening was maximal (70 degrees) in all but one of the observed instances. Longer clinical follow-up is required, but the new integral monostrut Björk-Shiley prosthesis, with its important design changes and excellent hemodynamic performance, appears to be a promising aortic valve substitute.

Combined aortocoronary bypass and intraoperative transluminal angioplasty in left main coronary artery disease

Transaortic intraluminal angioplasty of the left main coronary artery by Grüntzig's technique has been used intraoperatively in 4 patients who underwent multiple aortocoronary bypasses. Angiographic and clinical results were excellent in 3 of them. It is suggested that this combined technique be used to obtain more complete revascularization at the time of coronary artery bypass. The technique is easy to perform without x-ray facilities in the operating room, and it seems reasonable to assume that it may improve the myocardial blood supply of those areas irrigated by small arteries originating between the stenosed main trunk and other subsequent lesions.

The use of pigtail catheters for retrieval of foreign bodies from the cardiovascular system

Snare retrieval of foreign bodies is a common procedure but in certain cases, location of the foreign body requires another system. We present three cases in which only the use of a pigtail catheter gave a good grip for gentle traction and removal or repositioning of the foreign body. A careful review of the world literature up to December 1982 gave rise to two previous similar reports. Both our experience and that found in the literature seem to suggest that in cases where there are no free ends to snare, pigtail catheters may be the first instrument used to start retrieval.

Coronary angioplasty in iatrogenic coronary artery stenosis

Iatrogenic coronary artery stenosis as a serious complication of aortic valve procedures is a difficult condition to solve. We present a case in which both ostia were involved. As the patient refused reoperation, percutaneous transluminal coronary angioplasty (PTCA) was used.

Concealed atrial electrical activity

In the following paragraphs we describe a case diagnosed clinically and haemodynamically as a cardiomyopathy. Atrial flutter which was not in evidence in the standard ECG was diagnosed by the use of a new technique of amplification and filtering of special surface leads (T.A.F.). The diagnosis was later confirmed by means of special internal techniques (intra-atrial ECG and His bundle recording). The existence of a subpraventricular rhythm, probably sinusal, and also unapparent in the standard ECG, was observed by using the same method after electrical defibrillation. We comment on the extreme rareness of discovering concealed atrial rhythms and their possible explanation, and we emphasize the usefulness of the T.A.F. technique in their diagnosis.

Dissociation between indices of pump performance and contractility in patients with coronary artery disease and acute myocardial infarction

An analysis of ventricular performance comparing pump function and muscle function indices was performed in 13 patients with acute myocardial infarction, ten patients with normal coronary arteries, and 15 patients with coronary artery disease. Pump function was described by plotting left ventricular stroke work index as a function of left ventricular end diastolic pressure. This description provided a clear separation between normal patients, and surviving and nonsurviving patients with acute myocardial infarction. Values of contractile element velocity (VCE5 as an estimate of Vmax) did not separate between normals and surviving or nonsurviving patients with acute myocardial infarction. In 15 patients with acute coronary artery disease there was no correlation between values of VCE5 and the ventricular function curve. Changes in performance following the stress of ventriculography, angiotensin infusion, or isometric hand grip exercise also did not show any correlation between pump function and muscle function indices. It is concluded that pump function indices are a better indicator of ventricular performance in patients with acute myocardial infarction and coronary artery disease.

Hemodynamic and metabolic responses to vasodilator therapy in acute myocardial infarction

Hemodynamic effects of vasodilator therapy (phentolamine or nitroprusside) were studied in 38 patients with acute myocardial infarction (AMI). Cardiac metabolism was studied in 19 of the 38 patients. According to the initial level of left ventricular filling pressure (LVFP) and left ventricular stroke work index (SWI), patients were divided into three groups: Group I-nine pa- tients with LVFP 15 mm Hg or less; Group II-14 patients with LVFP > 15 mm Hg and SWI >20 g-m/m 2 ; Group III-15 patients with LVFP > 15 mm Hg and SWI < 20 g-m/ m 2 . In Group I most patients were clinically uncomplicated. In Group IL most patients had clinical left ventricular failure including one patient who had clinical features of cardiogenic shock. Group III patients all had severe left ventricular failure, with eight patients in clinical shock.

In all groups LVFP, pulmonary artery pressure, right atrial pressure, and systemic and pulmonary vascular resistance decreased significantly with vasodilator therapy with only a slight to moderate decrease in arterial pressure. In Group I patients SVI decreased (-7%) together with an increase in heart rate. Significant improvement in left ventricular performance, however, was observed in Groups II and III as indicated by increased stroke volume index (SVI) and cardiac index (CI) and decreased LVFP. The increase in SVI and CI was of similar magnitude in both Group LI (SVI +18%, CI +24%) and Group III (SVI +28%, CI +29%) patients, a change suggesting that vasodilation thereby may be applicable and beneficial even in the presence of severe depression of cardiac performance.

Improved left ventricular performance in group II and III patients was accompanied by a slight decrease in coronary blood flow, myocardial oxygen consumption, and transmyocardial oxygen extraction. There was no change in myocardial lactate metabolism in any group. In vitro studies in isolated cat papillary muscle preparations showed no direct positive inotropic effect of either phentolamine or nitroprusside. Thus, significant improvement in left ventricular performance occurs during vasodilator therapy in patients with AMI and elevated LVFP, even in the presence of severe depression of cardiac performance. Furthermore, this improvement is not accompanied by increased metabolic cost. Vasodilator therapy, therefore, may have an important role in the treatment of pump failure complicating myocardial infarction.