[Why do patients discontinue their drugs?]

BACKGROUND

Preventing or treating an illness just as avoiding its complications depend on the proper continuity of the intake of medication. Patients who discontinue their drugs unilaterally could call the resuIt of treatment into question.

METHODS

Practising doctors who have the patients' trust asked, whether patients had discontinued their drugsandwhytheydidso.

RESULTS

250 patients from 19 doctors' offices admitted having discontinued, 54.8% of them because of adverse drug reactions, and 45.2% because of other reasons. Most of the adverse drug reactions were listed in the prescribing information, but there were also adverse events, which were not listet, and which could have a signal effect. Patients named a lot of different reasons for discontinuation not related to adverse drug reactions. The reasons were comprehensible and possibly could be avoided.

CONCLUSION

Physicians should call attention to possible adverse events and should show up a benefit-risk profile. Reasons for discontinuation different from adverse drug reactions require physicians' efforts, but also help from family members, pharmacist, health insurance and health authority.

[Why do patients discontinue their drugs?]

BACKGROUND

Preventing or treating an illness just as avoiding its complications depend on the proper continuity of the intake of medication. Patients who discontinue their drugs unilaterally could call the result of treatment into question.

METHODS

Practising doctors who have the patients' trust asked, whether patients had discontinued their drugs and why they did so.

RESULTS

250 patients from 19 doctors' offices admitted having discontinued, 54.8% of them because of adverse drug reactions, and 45.2% because of other reasons. Most of the adverse drug reactions were listed in the prescribing information, but there were also adverse events, which were not listet, and which could have a signal effect. Patients named a lot of different reasons for discontinuation not related to adverse drug reactions. The reasons were comprehensible and possibly could be avoided.

CONCLUSION

Physicians should call attention to possible adverse events and should show up a benefit-risk profile. Reasons for discontinuation different from adverse drug reactions require physicians' efforts, but also help from family members, pharmacist, health insurance and health authority.

[Do patients understand special terms in the product information?]

The product of information for drugs is essential for the determinant use of drugs to guarantee the efficacy and safety of drugs. Supposition is the comprehension of special terms. The interviews of 277 patients by chance with 433 questionnaires (3313 questions) in the private practices showed that only a quarter of the special terms could be understood. Therefore it is necessary that the special terms must be translated to German or should be explained.

[Can cardiovascular diseases be reduced over 80% by a "superpill"? Review on the epidemiological study from Wald and Law, 2003]

As a consequence of our "western" diet and lifestyle, the risk for cardiovascular diseases is increased in the western world. It can be decreased by influencing the LDL-cholesterol values, the blood pressure and the platelet aggregation. It is, however, not proven that lowering of serum homocysteine levels reduces the risk forcardiovascular diseases. Wald and Law suggest in their epidemiological study a polypill, which has as its ingredients a statin, an anti-hypertonic drug, folic acid, and aspirine. Overall, the risk reduction by a polypill is overestimated, since a threshold is currently not existing, in all drugs side effects and interactions are possible, pharmaceuticals are only labelled for specific indications, and with missing efficacy there could be a negative risk-benefit-relation. Indeed, a combined therapy with different drugs is in place in patients with higher risk and for secondary prevention, which is already risk-adjusted. The use of effective drugs, however, in patients without evidence of a positive risk-benefit-relation and without medical control cannot be justified. Therefore, the application of the polypill for subjects beyond 55 years of age is an illusion; by contrast, treatment of patients with a high risk for atherosclerotic diseases is already reality.

[Diagnosing magnesium deficiency. Current recommendations of the Society for Magnesium Research]

The cardiovascular risk increases with decreasing serum levels of magnesium, and this already at concentrations within the previous reference range (0.70-1.10 mmol/L). For this reason, the Society for Magnesium Research has updated its 1986 recommendations for the diagnosis of magnesium deficiency. The diagnosis is based on the patient's history, his clinical symptoms, and the results of clinical-chemical investigations of plasma/serum and urine. Further diagnostic methods used include the determination of ionized serum magnesium and the magnesium retention test. The optimal serum magnesium concentration is > 0.80 mmol/L.

[Early hemodynamic cardiovascular reactions to nonionic low-osmolar contrast media in coronary angiography]

During the last 20 years there was an essential improvement in the tolerance of intravasal contrast media, leading to the nonionic low osmotic contrast media. In 26 consecutive patients with different stages of coronary heart disease the nonionic low osmolar contrast media iopamidol (Solutrast) and iopromide (Ultravist) were tested during coronary artery and left ventricular angiography. In both contrast media there were practically identically only slight early haemodynamic reactions with a decrease of heart rate, systolic pressure in the left ventricle, pressure in the aorta and an increase in pressure in the pulmonary artery and partly in cardiac output. These reactions are probably due to higher osmolality in comparison with blood. Therefore, further development of isotonic contrast media would be necessary.

[Acute and delayed aortocoronary bypass operations following transluminal angioplasty]

Since 1980 348 PTCAs and 1288 CABs were performed at our institution (relation 1:4). In 15 cases (4.3%) emergency CAB was necessary because of complications encountered with PTCA. Two patients died, i.e. a mortality rate of 43.3% out of the emergency CABs or 0.6% out of the PTCA group; in 46.6% myocardial infarction occurred. In the same period 12 patients received CAB because of unsuccessful PTCA after a mean time of 4.6 months without increased operative morbidity. Interdisciplinary indication and experience, operation permanence and temporary coronary perfusion may decrease the complication rate.

[Early hemodynamic reactions of an ionic low osmolar and a nonionic contrast medium]

In eighty patients with different cardiac diseases the theoretically claimed reduced cardiovascular side effects in ionic and non-ionic low osmolar contrast media compared to those in conventional ionic and high-osmolar contrast media were tested during heart catheterization. The randomized application showed that there were only few reactions during left ventricle angiography and they did not differ between various ejections, while during selective coronary angiography in most cases heart rate and aortic pressures dropped significantly (p less than 0.05). These alterations were significantly (p less than 0.05) stronger in the conventional ionic and high-osmolar ioxitalamat (Telebrix 350) than in the ionic and non-ionic low-osmolar ioxaglat (Hexabrix) or non-ionic low-osmolar iopamidol (Solutrast 370).

Acute and chronic effects of the beta-receptor blocker mepindolol on hemodynamics and the portal circulation

After administration of mepindolol, a reduction of the portal pressure was demonstrated in an acute study in six patients with varying degrees of cirrhosis of the liver and in a chronic study in 5 patients. The reduction of the portal pressure did not correlate very closely with the decrease in the cardiac output. It is therefore assumed that a beta 2-receptor effect with dilatation of the splanchnic vessels is the main mechanism. However, further studies are required to clarify the situation unequivocally. The properties of mepindolol (intrinsic sympathomimetic activity, slight negatively inotropic effect, non-selective action, primarily renal elimination) appear to be advantageous in this respect.

Comparative clinical and hemodynamic investigations on two beta-receptor blocking agents (pindolol and mepindolol) in normal subjects

Clinical and hemodynamic investigations of the effects of the new beta-receptor blocking agent mepindolol were compared with those of pindolol in studies with seven male subjects 23-34 years old. Mepindolol was found to be more effective in lowering the resting and exercise heart rate at lower dose levels. A more pronounced increase in right ventricular and pulmonary artery pressure was observed on exercise, but there was no difference between the two drugs in the effect on cardiac output. Thus mepindolol seems to have a greater effect on chronotropic than on inotropic receptors. This means that the drug can be given to patients with exertional angina without increasing the risk of cardiac decompensation.

[Experimental and clinical investigations on reapplicability of resterilized intravascular catheters (author's transl)]

Catheters for cardiovascular and other angiographic investigations can be resterilized by ethyl-oxide. The procedure of sterilisation has to be controled permanently. Reapplicability of catheters has become quite common because of the high price of new catheters. In spite of optimal resterilisation and permanent controll some patients still get fever attacks, because endotoxins cannot be eliminated by this method.

[Echocardiographic septal motion in 50 patients with coronary artery disease. A correlative study with coronary angiographic findings (author's transl)]

The literature about pathological septal motion in coronary artery disease is contradictory. Purpose of this study was to reveal the sensitivity and specificity of the echocardiography for diagnosis of stenoses and occlusions (S/O) of the left anterior descending artery (LAD). 50 patients with CAD were studied using coronary angiography and echocardiography. In 32 of the cases a critical stenosis (over 70% narrowing) of the LAD was present. History of old infarction was found in 80% of the patients. Angina pectoris was absent at the time of the investigation. It was proven that the sensitivity of the echocardiography for the diagnosis of coronary stenoses and for proximal and peripheral LAD-S/O is not high (44%-61%). 50 percent of all LAD-S/O and 61% of the proximal LAD-S/O have a pathological septal movement. In presence of a pathological septal motion, however, it may be concluded that there is a critical stenosis in one or more of the three main coronary arteries (predictive value 91%). The diagnosis of the localization of the occlusion by echocardiography is not possible. 1/3 of peripheral LAD-S/O also lead to a dyscinetic septum which mostly is found in proximal LAD-S/O. The number of false positive (pathological) echocardiographic septal dyscinetic motion is low (12%). The sensitivity of echocardiographic method for diagnose of coronary alteration is increased when using the differentiation between stenosis and occlusion of LAD. By that it can be revealed that full occlusions of the LAD lead in 80% to septal dyscinetic motion, whereas stenoses are only rarely combined with pathological septum (36%). It is concluded that not only the localization but predominantly the degree of the vessel-narrowing influences the septal movement. Perhaps these findings may help to declare the contradictory results in literature.

Cytomegalovirus myocarditis

A male patient, aged 31 years, with a cytomegalovirus (CMV) myocarditis is described, who showed a high IgM antibody titer for cytomegalovirus infection of 1:1,024 and a rise of the titer for complement-fixing antibody from 1:< 16 to 1:256. CMV could be isolated from the urine. Investigations for other etiological factors were negative, and we assumed a connection between the cytomegalovirus infection and the myocardial involvement.

[Prodromal symptoms of acute myocardial infarction (author's transl)]

Enquiry among 85 patients who had suffered myocardial infarction revealed prodromal symptoms in 69%, which consisted of a gradually developing angina in 28% and sudden severe thoracic pains in 31%. The localization of the pain in the prodrome coincided with that of the infarction in 82%. Prodromes occurred most frequently in patients with infarction of the anterior wall. Prodromal patients showed hyperlipidemia more frequently as a risk factor. Cardiac arrhythmias, cardiogenic shock, indications of incipient aneurysm of the heart wall and signs of heart failure were no less frequent in patients with and without prodromal symptoms. 42% of the patients sought medical attention because of the prodromal complaints. The therapeutic possibilities arising from this are discussed.

[Clinical and hemodynamic studies before and after mitral valve replacement (author's transl)]

Clinical and hemodynamic studies were carried out before and after replacement of stenotic mitral valves in 17 patients, 10 of whom received Björk-Shiley (low profile mechanical) prostheses and 7 who received (porcine heterograft) bioprostheses. Mitral valve replacement led to amelioration of symptoms, improvement of phonocardiographic findings and, partially, to a lowering of pressure in the pulmonary circulation, augmentation of cardiac output, lessening of the pulmonary arteriolar and mitral valvular resistances as well as incrementation of mitral valve orifice area. Preexistent ECG changes, radiologic heart size, right ventricular filling pressure and stroke volume remained unaltered. In consideration of variables such as prosthetic size, severity of the disease and post-operative follow-up periods, the results obtained with both types of prostheses were comparable. The prostheses, however, inherently are responsible for a moderate degree of mitral stenosis which compromises exercise capacity and generally does not lead to normalization of pressure in the pulmonary circulation. Irreversible myocardial damage appears responsible for the fact that electrocardiographic abnormalities, the heart size, the right ventricular filling pressure and stroke volume remain unaltered postoperatively. Thus, patients who have undergone mitral valve replacement continue to require limitation of physical activities, a tailored medical regimen and close cardiologic follow-up.

[Myocardial infarction "with angiographically normal coronary arteries (author's transl)]

Within a cohort of 121 patients with clinical picture and electrocardiographic pattern of myocardial infarction four cases (3%) had normal coronary arteried demonstrated by selective coronary angiography. Two patients revealed no risk factors, two patients were heavy cigarette smokers. Mean age of patients was 34 years. Exact analysis of clinical, hemodynamic and angiographis data confirmed assumption of regional myoaggressive myocarditis as the underlying disease in one patient and suggested regional myocarditis with high probability in another case. The two other patients however could not be classified as having coronary or primary myocardial disease. The investigation suggests that some cases with the clinical and electrocardiographic pattern of "myocardial infarction" with normal coronary arteries may be due to regional myoagressive myocarditis.

[Heart size and left ventricular function in coronary artery disease. II. Heart volume, coronary morphology and laevocardiogram (author's transl)]

We have investigated the possible relationship between the radiogically determined cardiac volume and the coronary angiogram and laevocardiogram. There was no relationship between cardiac size and coronary angiogram. Independently from the number of coronary vessels involved, we found normal sized hearts in patients without ECG-evidence of myocardial infarction, and enlarged hearts in patients with ECG-evidence of myocardial infarction. There was a significant, though loose relationship between the cardiac volume and the endsystolic and enddiastolic volumes (r=0.73 and 0.55 respectively) and the ejection fraction (r=0.69) as determined by laevocardiography. The critical value of the cardiac size, about which one encounters an increased number of abnormal volume parameters, was the upper boundary of 1-SD. Using this value we found a specifity of 81% and a sensitivity of 74% for the heart volume as a predictor of a pathological ejection fraction. On the other hand, using the upper boundary of 2-SD as a critical value, there was a sensitivity of only 58%, but a specificity of 92%. Only 11% of the patients with a cardiac size in the lower range of normal or below had an ejection fraction below 50%. Therefore the radiologically determined heart size is a simple, in daily practive acceptable method to assess and follow up left ventricular function in coronary patients.

[Heart size and left ventricular function in coronary artery disease: I. Heart size, exercise tolerance, cardiac output and filling pressures (author's transl)]

The possible relationship between the cardiac volume, as determined radiologically in the supine position in 119 patients with angiographically proven coronary artery disease, and the results of ergometry and balloon catheterization was investigated. There was no relationship between the heart size on the one side and the maximum exercise tolerance and the maximum cardiac output on the other, except for the fact, that these parameters tended to decrease with increasing heart size. This was especially true in patients with angina. The maximum cardiac output of patients with angina was always below the value of patients without angina but comparable heart size. Reduced cardiac output under exercise (exertional cardiac insufficiency) was present in 50% of patients with enlarged hearts but already in 22% of patients with heart volumes in the lower range of normal. The diastolic pulmonary artery pressure, determined under exercise, was the only parameter with a significant relationship to the heart size: The larger the heart size, the higher the diastolic pulmonary artery pressure. On the other hand: the diastolic pulmonary artery pressure at rest was abnormal with significant frequency only, when the heart was enlarged. Our data suggest, that the hemodynamics are determined by 2 factors: Myocardial scarring secondary to infarction and coronary insufficiency (ischemia). Of these two factors only the former influences cardiac size. Therefore, determination of the heart volume helps evaluating the respective role of these two factors in individual cases.

[The importance of heterologous implants in cardiovascular surgery (author's transl)]

The importance of heterologous transplants in the substitution of heart valves in cardiac surgery and the substitution or bypassing of displaced arteries of the thigh in vascular surgery is discussed with reference to some results and developmental considerations. In addition to the alloplastic valve material, heterologous bioprosthesis from glutaraldehyde-fixed pig's valves has proved useful to an increasing extent for the substitution of diseased and functionally impaired heart valves. The results of followup examinations show equally favorable results in comparison with the alloplastic prosthesis. In vascular surgery, the calf collagen prosthesis has proved a real alternative to the alloplastic Dacron prosthesis at the level of the thigh.

Myocardial oxygen consumption and substrate uptake in man during physiological and pathological volume load

It is shown in trained and untrained healthy individuals that the energy requirement of the physiologically hypertrophied heart is lower at rest and even more pronounced during submaximal heavy exercise compared to the non-hypertrophied state. This difference exceeds the changes which could have been anticipated by deviations in hemodynamics and total heart weight. In patients with mild or moderate aortic insufficiency the energy expenditure of the pathologically hypertrophied heart per unit tissue mass is comparable to the non-hypertrophied state at rest or during exercise. It is increased in severe aortic regurgitation or additional myocarditis. The transition from compensation to failure may be associated with a steep decreased of the metabolic and flow reserve of the whole heart.

Studies on the regulation of myocardial blood flow in man. I.: Training effects on blood flow and metabolism of the healthy heart at rest and during standardized heavy exercise

In a comparative study 11 athletes and 11 untrained students were investigated at rest, of these 6 trained and 5 untrained individuals during exercise as well. Myocardial blood flow was measured by the argon method. Myocardial oxygen consumption, myocardial substrate uptake of glucose, lactate, and free fatty acids and cardiac output were determined by the direct Fick principle. Exercise was standardized according to 65% of an individual's maximal oxygen uptake (delta VO2 max). Coronary flow reserve was determined by dipyridamole injections. All measurements were made during hemodynamic and respiratory steady-state conditions with the subject in a supine position. At rest, myocardial blood flow and myocardial oxygen consumption were significantly lower in trained subjects compared to the untrained ones. These differences were more pronounced during heavy exercise. They cannot be explained completely by hemodynamic parameters. - During exercise, myocardial substrate uptake shifted to a predominant lactate uptake of almost 90% of total substrate uptake. Total substrate uptake as well as lactate uptake correlated significantly with myocardial oxygen. - Coronary flow reserve was lower in the trained group. It is concluded that the heart muscle of a trained individual requires less energy at a given work load than in the untrained state.

[Substitution of the aortic value in florid bacterial endocarditis and severe aortic valvular insufficiency (author's transl)]

Urgent operation for replacement of the aortic valve for the correction of a severe, increasing hemodynamic impairment of the output of the heart and for the removal of the septic focus in florid bacterial aortic endocarditis must be carefully thought over. 3 of our own 7 patients died. The indication is to be made largely on hemodynamic grounds when the clinical symptoms are quite clear without preoperative catheter diagnosis. Preliminary specific treatment with antibiotics and intensive follow-up treatment is necessary. Preoperative identification of bacteria in the blood, just like identification of bacteria on the excised valve, is only possible in some of the cases.

[Clinical and hemodynamic aspects of myocardial diseases (author's transl)]

Definition, arrangement into primary and secondary forms and classification of myocardial diseases are used irregularly in the literature. The great variety of clinical and hemodynamic parameters are shown with reference to our own patients and an attempt is made to arrange them in individual types. Followup examinations show that signs of congestive failure, heart size and other clinical and hemodynamic parameters may be considerably altered. For this reason it is proposed to describe myocardial diseases accoridng to clinical and hemodynamic parameters in order to obtain a closer insight into the pathomechanism of these diseases.