Evaluation and prognostic significance of left ventricular diastolic function assessed by Doppler echocardiography in the early phase of a first acute myocardial infarction

AIM: To study the prognostic significance of left ventricular diastolicfunction evaluated by transmitral and pulmonary venous flowvelocities obtained in the early phase of a first acute myocardialinfarction in relation to later development of congestive heartfailure. METHODS: Pulsed Doppler echocardiography of transmitral and pulmonaryvenous flow was assessed in 65 consecutive patients with a firstmyocardial infarction within 1 h of arrival in the coronarycare unit. RESULTS: A univariate regression analysis identified age, left ventricularejection fraction 45%, mitral E deceleration time 130 ms, E/Aratio >1·5, peak pulmonary venous atrial flow velocity30 cm . s^–1 and a difference between mitral and pulmonaryvenous atrial flow duration >0 ms as variables significantlyrelated to the development of congestive heart failure. However,in a multivariate analysis only mitral E deceleration time 130ms and age were significant independent variables related tothe development of congestive heart failure during the firstweek following a first acute myocardial infarction. CONCLUSION: Assessment of left ventricular diastolic function complementsmeasurements of systolic function in the evaluation of cardiacfunction, and mitral deceleration 130 ms best identifies patientsat risk of development of congestive heart failure followingacute myocardial infarction.     

Lifestyle and risk factor management and use of drug therapies in coronary patients from 15 countries. Principal results from EUROASPIRE II Euro Heart Survey Programme

Aims The principal aim of the second EUROASPIRE survey was todetermine in patients with established coronary heart diseasewhether the Joint European Societies' recommendations on coronaryprevention are being followed in clinical practice. Methods This survey was undertaken in 1999–2000 in 15European countries: Belgium, Czech Republic, Finland, France,Germany, Greece, Hungary, Ireland, Italy, the Netherlands, Poland,Slovenia, Sweden, Spain and the U.K., in selected geographicalareas and 47 centres. Consecutive patients, men and women 70years were identified retrospectively with the following diagnoses:coronary artery bypass graft, percutaneous transluminal coronaryangioplasty, acute myocardial infarction and myocardial ischaemia.Data collection was based on a review of medical records andinterview and risk assessment at least 6 months after hospitaladmission. Results 8181 medical records (25% women) were reviewed and 5556patients (adjusted participation rate 76%) interviewed. Recordingof risk factor history and risk factor measurement in hospitalnotes was incomplete, particularly for discharge documents.At interview (median time 1·4 years after hospital discharge),21% of patients smoked cigarettes, 31% were obese, 50% had raisedblood pressure (systolic blood pressure 140mmHg and/or diastolicblood pressure 90mmHg), 58% had elevated serum total cholesterol(total cholesterol 5mmol.l^–1) and 20% reported a medicalhistory of diabetes. Glucose control in these diabetic patientswas poor with 87% having plasma glucose >6·0mmol.l^–1and72% 7·0mmol.l^–1. Among the patients interviewedthe use of prophylactic drug therapies on admission, at dischargeand at interview was as follows: aspirin or other antiplateletsdrugs 47%, 90% and 86%; beta-blockers 44%, 66% and 63%; ACEinhibitors 24%, 38% and 38%; and lipid-lowering drugs 26%, 43%and 61%, respectively. With the exception of antiplatelet drugs,wide variations in the use of prophylactic drug therapies existbetween countries. Conclusions This European survey of coronary patients showsa high prevalence of unhealthy lifestyles, modifiable risk factorsand inadequate use of drug therapies to achieve blood pressureand lipid goals. There is considerable potential throughoutEurope to raise the standard of preventive cardiology throughmore effective lifestyle intervention, control of other riskfactors and optimal use of prophylactic drug therapies in orderto reduce coronary morbidity and mortality.     

Haemodynamic findings in experimental right ventricular ischaemia after right coronary arterial ligation

Acute ischaemia limited to the free wall of the right ventriclewas produced by right coronary arterial ligation (RCAL) in 20dogs. Contrast M-mode and cross-sectional echocardiography wasperformed in 7 cases to investigate the presence of tricuspidinsufficiency. The haemodynamic findings obtained with an openpericardium at 15 to 30 min showed increases in right (l.20.5to 2.70.7 mmHg, P0.01) andleft (5.0 0.8 to 6.60.9 mmHg, P005)ventricular end-diastolic pressures, and decreases in heartrate (1394.9 to 1195.1 bpm, P0.01), cardiac index (1066.6 to817.3 ml min^–1 kg^–1, P001), stroke index (79 6 to72 8 ml x 100 beat^–1 kg^–1, P0.02), right (23.8l.5to 19.41.5 mmHg, P0.01) and left (1097.2 to 958.2 mmHg, P005)ventricular systolic pressures and right ventricular strokework index (18.32.4 to 11.41.8 g m kg^–1, P0.01). In 6of 15 cases the 'y' descent became deeper than the 'x' descentin right atrial pressure (RAP). Tricuspid insufficiency gradeI–II/IV was present in 3 of 7 cases, 2 of them with a'y'>'x' in RAP. Right ventricular mechanical alternans, probablysecondary to a decrease in contractility, appeared in 10 of20 cases after RCAL. Closure of the pericardium exaggeratedthe haemodynamic alterations and a dip-plateau appeared in 2cases on the right ventricular pressure curve. We conclude thatsignificant aemodynamic alterations in right ventricular functionare produced by RCAL in dogs, and they are exaggerated afterclosing the pericardium.     

Determination of left ventricular wall thickness and muscle mass by intravenous digital subtractionangiocardiography: validation of the method

Left ventricular (LV) wall thickness and muscle mass are importantmeasures of LV hypertrophy. In 24 patients LV end-diastolicwall thickness and muscle mass were determined (two observers)by digital subtraction angiocardiography (DSA) and conventionalLV angiocardiography (LVA). Wall thickness was determined overthe anterolateral wall of the left ventricle according to thetechnique of Rackley (method 1) or by planimetry (method 2).Seventeen patients were studied at rest and seven during dynamicexercise. Wall thickness correlated well between LVA and DSA;the best correlations were obtained by a combined subtractionmode using either method 1 or 2 (method 1, r0–80; method2,r0. 75). The standard error of estimate of the mean (SEE) wasslightly lower for method 2 ( 10%) than for method 1 ( 13%).DSA significantly overestimated wall thickness by 5–7%with method 1 and underestimated by 12–14% with method2. Muscle mass correlated well between LVA and DSA; the SEEwas 15% for method 1 and 12% for method 2. Overestimation ofmuscle mass by DSA was 7–11% with method 1 and underestimationwas 13–15% with method 2.It is concluded that LV wallthickness can be determined accurately by DSA with an SEE rangingbetween 10 and 13%. Determination of LV muscle mass is slightlyless accurate and the SEE is slightly larger ranging between13 to 17%. With method 1, wall thickness and muscle mass wereover estimated and with method 2 underestimated.     

Protective effect of beta-blockade on dipyridamole-induced myocardial ischaemia: Role of heart rate

This study was designed to investigate the effect of heart ratechanges on dipyridamole echocardiographic tests in patientswith coronary artery disease treated with propranolol. We prospectively studied 12 patients (8 men and 4 women; meanage 56.5 ± 8.7 years) selected by: (a) angiographic evidenceof significant coronary artery disease; (b) adequate echocardiographicwindow; (c) positive dipyridamole echocardiography test resultsin baseline conditions (step I); (d) test reproducibility inthe absence of treatment; (e) negative dipyridamole echocardiographytest results after 7 days of treatment with propranolol (120mg. day^–1) in twice divided doses daily (step II). In all patients treated with propranolol, dipyridamole echocardiographictesting was repeated 24 h after the last negative test. In thesepatients, transoesophageal atrial pacing was performed at peakdipyridamole infusion to increase heart rate to values similarto those observed at baseline (step III). At baseline, heartrate and rate-pressure product were significantly lower in patientstreated with propranolol (–20.3% and –22.5% in groupII, P<0–001 vs step I; –24.3% and –26.4%in group III, P<0.05 vs step I), but the different treatmentsdid not produce significant differences in systolic and diastolicblood pressure. At peak dipyridamole infusion, heart rate andrate-pressure product increased with either placebo or propranololtreatments with respect to baseline, while remaining significantlylower with propranolol as compared to placebo ( –29.6%and –29.5% in step II, P<0001). During treatment withpropranolol plus transoesophageal pacing to maintain heart rateat values attained with placebo, the rate-pressure product didnot change significantly with respect to placebo, nor did systolicblood pressure. Transoesophageal atrial pacing performed duringpropranolol treatment to restore heart rate to baseline valuesdid not affect the dipyridamole echocardiographic test in eightpatients (group I), and induced transient wall abnormalitiesin four patients (group II) (P=ns). Our data suggest that the anti-ischaemic effect of propranololin man is not correlated only to reduction of heart rate.     

Central haemodynamic effects of metoprolol early in acute myocardial infarction. A placebo controlled randomized study of patients with low heart rate

The central haemodynamic effects of metoprolol in patients withacute myocardiol infarction and with heart rate 65 beats min^–1have been investigated in a randomized double-blind trial. Theaim was to study the tolerance in this selected patient groupand to assess possible differences in haemodynamic responseamongst patients with initially higher heart rates. Exclusioncriteria were: treatment with beta blockers; heart rate 65beats min^–1 systolic blood pressure 110 mmHg; and physicalsigns of serious heart failure. Following pulmonary artery catheterization,22 patients were randomized to metoprolol 15 mg i. v. + 50 mgq.i.d. orally ( N = 12) or placebo (N = 10). Central pressuresand cardiac output were recorded before and during the 24 hoursafter drug administration. There was a significant fall in heartrate, cardiac index, rate pressure product and stroke work indexof 10–20% in the metoprolol, compared with the placebogroup. The differences were most pronounced immediately afterthe metoprolol injection. The pulmonary artery capillary wedgepressure was not significantly changed. The overall haemodynamicresponse to metoprolol was similar to that reported in patientswith acute myocardial infarction and heart rate above 65 beatsmin^–1 Tolerance was good.     

Subjective symptoms and well-being differ in women and men after myocardial infarction

The frequency of subjective cardiac and psychological complaintsamong men and women a year after a confirmed diagnosis of myocardialinfarction (MI) were compared. Among 660 survivors, 595 patientscompleted mailed questionnaires at home one year after the MI.There were 421 men, mean age 67.1±10.7 years, and 174women, mean age 72.1±10.6 years. Controlling for the significantly higher mean age among thewomen, the latter more often had a previous history of anginapectoris, 54.6% (P0.05) versus 42.9%, and heart failure, 24.7%versus 13.5% (P0.01). Despite these facts, the women were significantlyless often referred to CCU, 82.2% versus 91.7% (P0.05). Oneyear after the MI, controlling for differences in age and co-morbidity,women reported significantly higher frequencies of psychologicaland psychosomatic complaints, including sleep disturbances.These differences may have clinical implications for diagnosisand treatment of women with coronary heart disease.     

Successful radiofrequency ablation of accessory pathways with the first energy delivery: the anatomic and electrical characteristics

Successful ablation of accessory pathways has been achievedat the first energy delivery site in some patients, but factorspermitting success at the first site are unclear. Accessorypathway location, surface and endocardial electrogram characteristicsin each location were analysed and compared between the patientswith first site block (group A, 34 patients) and those in whommultiple sites (median seven sites) were required (group B,133 patients). No patients with right free-wall pathways hadfirst site block. In group A surface electrocardiograms weremore pre-excited (QRS duration: 132±20 vs 120 ±l7ms, P<0·0l). For left free-wall and septal pathways,the interval from the onset of the earliest delta wave on surfaceelectrocardiogram to local ventricular activation (QRS-V) wasmore negative and the local atrioventricular interval (AV) wasshorter in group A; the positive predictive value of a QRS-V0 ms, an AV 30 ms and the presence of a possible accessory pathwaypotential was 67% for left free-wall and of a QRS-V -10 ms withan AV 30ms was 100% for septal pathways. During retrograde mappingof concealed left free-wall and right anteroseptal pathways(first site block was not achieved in other locations) the positivepredictive value of a local ventriculoatrial interval 30 mswas 55%. Accessory pathway location correlated strongly with the chancesof first site block, suggesting that anatomical features areimportant. Maximizing pre-excitation may be of benefit in achievingfirst site block. Delivery of energy to a site with specialendocardial electrogram features was associated with an increasedlikelihood of first site block.     

Coronary risk factors in men occupationally exposed to vibration and noise

In a group of 481 men (group A ) exposed occupationally to vibration(exceeding by four times the permissible levels in the frequencyband 32–64–125 Hz) and noise (105–116 dB),and in a group of 303 men without contact with vibration andnoise at work (reference group R) the prevalence of coronaryrisk factors was assessed, Socioeconomic status, level of occupationalphysical activity and family history of heart disease were comparablein the two groups. Mean blood pressure values and the percentage with hypertensionwere significantly higher in the exposed than in the referencegroup(P0.01). Overweight and hypertrigliceridemia occurred lessfrequently in group A than in group R(P0.01 and P0.05 respectively).The prevalence of hypercholesterolaemia and smoking habits wassimilar in both groups. The results suggest that vibration andnoise may be factors which increase the risk of coronary heartdisease.     

Coronary risk factors in men occupationally exposed to vibration and noise

In a group of 481 men (group A ) exposed occupationally to vibration(exceeding by four times the permissible levels in the frequencyband 32–64–125 Hz) and noise (105–116 dB),and in a group of 303 men without contact with vibration andnoise at work (reference group R) the prevalence of coronaryrisk factors was assessed, Socioeconomic status, level of occupationalphysical activity and family history of heart disease were comparablein the two groups. Mean blood pressure values and the percentage with hypertensionwere significantly higher in the exposed than in the referencegroup(P0.01). Overweight and hypertrigliceridemia occurred lessfrequently in group A than in group R(P0.01 and P0.05 respectively).The prevalence of hypercholesterolaemia and smoking habits wassimilar in both groups. The results suggest that vibration andnoise may be factors which increase the risk of coronary heartdisease.     

Submaximal early exercise test compared to clinical findings for evaluation of short- and long-term prognosis after the first myocardial infarction

Clinical and ergometric data were derived from 1098 consecutiveexercise tests in patients with a first acute myocardial infarctionbetween 1974–1983. In 1992 a follow-up was performed inorder to analyse the importance of a submaximal early exercisetest, in combination with clinical data, for the predictionof short- and long-term prognosis of cardiovascular death. The relative value of 20 clinical variables, including medicalhistory, markers of infarction size, medication etc., and 28variables at exercise test were studied. Univariate, multivariateand survival analysis, for estimation of prognosis and independentprediction of cardiovascular death was used. Independent clinical risk factors for cardiovascular death were(1) Within 1 year: relative heart volume (ml.m^–2 bodysurface area) on chest X-ray. (2) Long-term mortality: maximumheart rate and relative heart volume, diabetes, age and digitalismedication. Independent exercise risk factors were: (1) Within1 year: heart rate, ventricular arrhythmia and ST depression 1 mm before exercise, diastolic blood pressure at maximum exerciseand target heart rate. (2) Long-term mortality: angina pectorisand/or ST depression 1 mm at maximum exercise. In subgroupsof patients with clinical risk factors, mortality risk increasedif there were signs of angina pectoris and/or ST depression 1 mm during exercise. The risk increased 100% in diabetics,91% with age >70 years, 58% with relative heart volume 500ml.m^–2 body surface area, 42% with heart rate 100 atadmission, and 34% with digitalis medication. No increase wasfound in the subgroup of patients without clinical risk factors. Thus, submaximal early exercise stress testing provides importantinformation for short- and long-term prognosis in patients afterthe first acute myocardial infarction compared to clinical evaluationalone.     

Lipoprotein(a) as a risk predictor for cardiac mortality in patients with acute coronary syndromes

Aims Raised lipoprotein(a) concentrations are considered to be arisk factor for atherothrombotic diseases. We examined whetherbaseline concentrations were a risk factor for an adverse outcomein patients admitted with acute coronary syndromes. Methods and Results Five hundred and nineteen patients admitted with suspected acutecoronary syndromes were studied and followed prospectively fora median of 3 years. The prognostic significance of a baselinelipoprotein(a) concentration of 30mg.dl^–1or lower forsubsequent cardiac death was assessed in patients with myocardialinfarction (266) and unstable angina (197) and compared withother variables in regression models. In patients with myocardialinfarction, a baseline lipoprotein(a) concentration of 30mg.dl^–1wasassociated with a 62% increase in subsequent cardiac death comparedto the lower concentration group (29·8% vs 18·6%,Log rankP=0·04). In a multivariate regression model abaseline lipoprotein(a) concentration of 30mg.dl^–1retainedits significance as an independent predictor of cardiac death(P=0·037). In patients with unstable angina, baselineconcentrations of 7·9mg.dl^–1were found to be significantpredictors of cardiac death in univariate (P=0·021) andmultivariate (P=0·035) regression models. Conclusion Baseline lipoprotein(a) concentrations in patients admittedwith acute coronary syndromes are associated with an increasedrisk of cardiac death. For patients with myocardial infarctiona concentration of 30mg.dl^–1appears appropriate as a riskdiscriminator; for patients admitted with unstable angina, however,much lower concentrations of lipoprotein(a) appear to be prognosticallyimportant.     

Autonomic balance in patients with angina and a normal coronary angiogram

The pathophysiology of angina pectoris in patients with a normalcoronary angiogram is not clear. Furthermore, the pathophysiologicalimpact of ST changes in syndrome X is controversial. The purposeof this study was to investigate cardiac autonomic function,by measuring 24 h heart rate variability, in patients with andwithout electrocardiographic evidence of ischaemia during exercise. Thirty-two patients with angina pectoris, a normal coronaryangiogram, echocardiogram, hyperventilation test and gastro-oesophagealinvestigation were studied. Fourteen healthy subjects servedas controls. Fifteen patients had significant ST segment depressionduring stress testing, whereas 17 had no electrocardiographicsigns of ischaemia. Heart rate variability was calculated as(1) mean RR= mean of all normal RR intervals, (2) the differencein mean RR level between when awake and when asleep (mean RRwake-sleep)—a tentative index of sympathetic activation,(3) the standard deviation (SD)—a broad band measure ofautonomic balance, and (4) a percentage of successive RR intervaldifferences 6% (pNN6%)—an index of vagal modulation. Thecoronary vascular resistance was measured at rest and duringpacing. Mean RR and autonomic indexes did not differ between patientswith a positive exercise test and controls (831/884 m 24 h SD125/134 m pNN6% 6.715.4%, respectively). Patients with a normalexercise test had shorter mean RR (758 ms vs 844 m P<0.05)and significantly reduced 24-h SD (103 ms vs 134 m P<0.05)than controls, whereas values for vagal index (6.5% vs 5.4%)did not differ from healthy controls. Mean RR wake-sleep alsotended to be lower in patients with a normal exercise test (–125 ms vs – 173 ms) compared to controls (P<0.1). Patientswith a positive exercise test had a significantly attenuatedreduction in coronary vascular resistance during pacing in comparisonto patients with a normal exercise test (–0.131–0.26mmHg x min. ml^{– 1}; P<0.05). The findings suggest the occurrence of general elevated sympatheticactivation in angina patients with a normal exercise test. Patientswith a positive exercise test exhibited no signs of autonomicdysfunction although these patients had altered coronary vascularresistance indicating microvascular angina. This supports thesuggestion that patients with a normal exercise test constitutean independent pathophysiological entity.     

Early administration of captopril and nitroglycerin in combination after acute myocardial infarction: an invasive haemodynamic study

The combination of captopril and nitroglycerin early after acutemyocardial infarction (AMI) could lead to a dangerous decreasein blood pressure coronary perfusion. To evaluate the safetyaspects and haemodynamic effects of this combination, we studied36 first ‘Q wave’ thrombolysed anterior wall AMIpatients during the 24 h following the onset of symptoms. Afterwards, thrombolysis patients received a continuous infusionof nitroglycerin and were submitted to pulmonary artery catheterization.Those patients with mean arterial pressure (MAP) 70 mmHg, cardiacindex 2.21. min^–1.m^–2, and wedge pressure 10 mmHgwere included and randomized to receive 6.25 mg of captoprilevery 6 h on the first day and 12.5 mg qid on the second f MAP 70mmHg (group 1). A second group (group 2) received a placebo.Haemodynamic parameters were determined after 1, 6 and thenevery 6 h up to 48 h after basal measurements. Significant differenceswere observed only for the MAP and the rate-pressure product(reduction in group 1 values, P <0.05). However, MAP wasmaintained within acceptable limits. Our data support the factthat the combination of captopril and nitroglycerin in the earlyhours of a non-complicated anterior wall AMI is safe, and couldguarantee its use in large clinical trials to determine theeffects on left ventricle remodelling and survival after AMI.     

Biplane transoesophageal echocardiography, transthoracic Doppler, and magnetic resonance imaging in the assesment of coarctation of the aorta

This study compared flow-sensitive magnetic resonance imagingwith biplane transoesophageal echocardiography in combinationwith continuous wave Doppler from the suprasternal notch inpatients with native coarctation or after surgical repair. Twenty patients (mean age 33 years, range 17–60) wereinvestigated, of whom 15 had undergone surgery at mean age 13years, range 5.43. Peak and mean flow in the ascending and descendingaorta as well as coarctation peak velocity were determined withthe magnetic resonance imaging phase contrast technique. Coarctationpeak velocity was also measured by Doppler from the jugulum.Magnetic resonance imaging axial sections as well as biplanetransoesophageal echocardiography were used to measure the smallestdiameter of the constricted segment. Sixteen healthy volunteers,mean age 36 years, range 22.63, provided reference values formagnetic resonance imaging determined volume of flow in theaorta. Peak flow in the descending aorta was 9.2 ±3.71.min ^{– 1} (reference 130 ± 2.5, P<0.01) and meanflow 3.1 ±0.9 I. min^{– 1} (reference 3.4 ±0.8,P>0.05). The ratio of descending-to-ascending peak flow was0.54 ±0.17 (reference 0.69 ± 0.10, P<0.01)and mean flow 0.68 ± 0.15 (reference 0.69 ± 0.08,P>0.05). The coarctation velocity was slightly higher withDoppler than with magnetic resonance imaging (+ 0.24 ±0.44 m. s^{– 1}, 95% confidence interval +0.45 to + 0.02m.s^{– 1}, P= 0.05). The coarctation diameter was slightlylarger with magnetic resonance imaging than with transoesophagealechocardiography (1.4 ±3.5 mm, 95% confidence interval+ 3.1 to – 0.3 mm, P= 0.11). Both methods are suitable for the assessment and follow-up ofcoarctation of the aorta Flow assessment with magnetic resonanceimaging provides a hitherto unavailable measure with which toassess the severity of obstruction.     

Balloon occlusion during coronary angioplasty as a model of myocardial ischaemia: reproducibility of sequential inflations

In order to evaluate the potential of balloon occlusion duringcoronary angioplasty as a model of myocardial ischaemia in manwe have measured coronary sinus blood flow (CSBF), myocardialoxygen consumption (MVO₂), lactate extraction (LER) and electrocardiographicchanges in 11 patients undergoing left anterior descending artery(LAD) angioplasty. Baseline measurements were made before ballooncrossing and between inflations. Four consecutive inflationseach of 60 s duration were made; 5 min return to baseline wasallowed between inflations. There was a significant reduction in CSBF and MVO₂ (ml min^–1)during inflations 2, 3 and 4 (CSBF: 121±6694±53,113±4999±42, 124±66102±41, P<0.02;MVO₂:11.3±6.6–9.1±3.9, 10.4±3.7–8.7±2.4,12.2±4.49.4±2.8, P<0.05). However during thefirst period of balloon occlusion there were inconsistent changesin coronary flow with an overall rise in mean flow (97±35128±80ml min^–1, P = NS) and an overall rise in mean myocardialoxygen consumption (9.6 ± 3.812.5 ± 7.5 ml min^–1,P = NS). There was lactate production during all four inflationsbut the changes during the first one did not achieve statisticalsignificance. These inconsistent changes during the first inflation were thoughtto be due to partial obstruction of the stenosis by the deflatedballoon before primary dilatation. The changes due to crossingand during the first two inflations were further investigatedin another group of 12 patients undergoing LAD angioplasty.Great cardiac vein flow (GCVF), CSBF, MVO₂ and LER were recordedat baseline, during crossing and during the first two inflations.With the deflated balloon across the stenosis there were nochanges in CSBF or MVO₂ but there was a fall in GCVF (103±2877±50,P = NS) and a significant fall in LER (77±5716±37,P<0.01). Although there was a fall during the first inflationin CSBF, GCVF, MVO₂ and lactate extraction none of these changeswere significant. During the second inflation these changeswere of greater magnitude and achieved statistical significance. While balloon occlusion during coronary angioplasty has thepotential of providing a model of ischaemia in man we have foundthe first inflation period unreliable, due to the variable degreeof occlusion by the deflated balloon. We suggest that only subsequentinflations after the primary dilatation are used for observations.These findings are of significance when evaluating the effectsof therapeutic interventions during PTCA. Various refinementsin measurements of the effects of ischaemia will improve thespecificity of the model.     

Age-related mortality, clinical heart failure, and ventricular fibrillation in 4259 Danish patients after acute myocardial infarction

AIMS: To evaluate the prognosis of patients 80 years old, we analyseda large, community-based population with acute myocardial infarctionwho received intensive observation and similar pharmacotherapyregardless of age. METHODS AND RESULTS: In a 12-year period, before the introduction of thrombolysis,4259 consecutive patients hospitalized with acute myocardialinfarction from the same hospital in Denmark were prospectivelyregistered. Their complications and mortality in hospital, and1 and 5 years after discharge were analysed retrospectively.Overall, in-hospital mortality was 11% for patients less than<50 years old, 22% for patients 60–69 years old and43% for patients 80 years old. Two thirds of patients 80 yearsold had heart failure, and cardiogenic shock was twice as commonin this age group than in patients 60–69 years. Heart failure was a strong independent risk, factor for post-dischargemortality, particularly in the oldest age groups. Four out ofeight patients 80 years survived one year if discharged aliveafter experiencing in-hospital ventricular fibrillation. CONCLUSION: The life-saving potential of preventing or treating heart failureseems considerable even in the oldest patient groups. Patients80 years old who survive in-hospital ventricular fibrillationhave an acceptable prognosis 1 year post-discharge.     

Rapid diminution of calcium in the myocardium by transfer to pericardial solutions: Myocardial dialysis

A new method is described for the controlled and specific depletionof calcium from the vascularly perfused heart of experimentalanimals by means of dialysis, using a pericardial solution. A 30–40ml isotonic phosphate buffer pH7.3 with a low Ca²⁺ and high Mg²⁺ concentration (0.2 and 2.7mM respectively) wasinserted into the pericardial cavity of anaesthetized dogs andkept therefor 10 or 60 min. The calcium content of the subendocardialand subepicardial halves of the left ventricular wall was similarlydecreased to about 70% (P<0.01) within 10 min and to 62%(P<0.001) at 60 min, compared to that of hearts dialysedfor60 min in a standard solution ofCa²⁺ 1.2 mM and Mg²⁺ 1 mM.Calcium content of the myocardium dialysed with low Co²⁺ anda standard Mg²⁺ solution decreased to only 75% (P<0.01)at 60 min. Similar changes of calcium were measured in otherparts of the heart. An increase in Co²⁺ concentration in the pericardial solutionwas observed at the same time as a decrease in calcium in themyocardium. The increase in Ca²⁺ reached about 0.7 mM at 60min, but decreased slightly, and finally, fell to 85% of pre-dialysisvalues at 60 min. It is concluded that this method of myocardial dialysis is effectivein reducing myocardial calcium and is influenced by the durationof dialysis and the Mg²⁺ content of dialysate.     

Nocturnal angina in patients with fixed coronary stenosis. Increased coronary vasoconstrictive sensitivity with independence of pacing ischaemic threshold

Atrial pacing and ergonovine tests were performed in 18 consecutivepatients with unstable angina at rest and significant coronaryartery stenosis ( 90% in one vessel in 16 patients). 13 ofthem also had exertional angina. 14 patients presented at leastone positive response (1.0 mm ST-segment shift) to pacing, witha heart rate (144±11 vs 75±13 beats min^–1,P<0.001) and double product (195±26 vs 108±32x 10^–2 P<0.001) significantly higher than during anginaat rest. In the ten patients who presented nocturnal angina,the incidence of positive response to pacing and the pacingischaemic threshold, tested on three different days, were similarto those seen in the remaining patients. In contrast, the ergonovinetest was positive in all patients with nocturnal angina (100%),who required a low dose (0.28±0.2 mg), but it was positivein only four (50%) of those without nocturnal angina, who neededa higher dose (0.55±0.12 mg, P<0.005). Therefore, in patients with severe coronary stenosis and exertionalangina, spontaneous episodes, including nocturnal angina, arenot related to increases in heart rate. The increased coronaryvasoconstrictive sensitivity found in these patients, particularlythose with nocturnal angina, was not dependent on the statusof the coronary reserve, which strongly suggests that changesin coronary tone, focal or diffuse, are involved in the mechanismsof these ischaemic events.     

Antihypertensive treatment with felodipine but not with a diuretic reduces episodes of myocardial ischaemia in elderly patients with hypertension

Episodes of transient myocardial ischaemia can frequently beobserved in hypertensive patients. To assess the effects ofantihypertensive treatment with the calcium antagonist felodipineor the diuretic combination hydrochlorothiazidel triamtereneon episodes of ischaemic-type ST-segment depression (ST-D),simultaneous ambulatory electrocardio-graphic and blood pressure(BP) monitoring was performed in 42 elderly hypertensives withoutmanifest coronary artery disease. All patients (mean age 79± 6 years, office BP 160/95 mmHg) were evaluated offany antihypertensive or anti-ischaemic therapy and after 3 monthstreatment with either felodipine or the diuretic (randomized,double-blind study) for episodes of significant ST-D (0.1 mV,duration 1 min, interval 1 min). The reduction in office BPand daytime ambulatory BP was similar for both agents, as wasa significant reduction in the heart rate x systolic BP product(DP) over 24 h (felodipine: 12 441 ±2076 vs 11 643 ±1953 mmHg. min^–1; P=0.048; diuretic: 12 366 ± 2782vs 11 062 ± 2012 mmHg. min^–1; P=0.003). While felodipinesignificantly decreased the total number of ST-D (from 40 tosix episodes; P=0.03), the total number of ST-D remained unchangedwith the diuretic (non-significant increase from 31 to 45 episodes;P=0.24). The same trend was observed for the number of patientswith ST-D. The ischaemic threshold, defined as DP at the onsetof the episodes of ST-D, increased with felodipine (12 171 ±340vs 13 770 ± 138 mmHg. min^–1) and decreased withthe diuretic (16 210 ±312 vs 14 092 ± 319 mmHg.min^–1). In conclusion, antihypertensive treatment withfelodipine reduces blood pressure and episodes of transientmyocardial ischaemia in elderly hypertensive patients, whilehydrochlorothiazidel triamterene increases these episodes despitea similar BP reduction. Felodipine may influence structuraland functional factors at the coronary micro circulation level.These mechanisms improve coronary blood flow and increase theischaemic threshold.