Clinical characteristics, aetiological factors and long-term prognosis of myocardial infarction with an absolutely normal coronary angiogram; a 3-year follow-up study of 91 patients.

OBJECTIVES: The purpose of this study was to evaluate the clinical outcome of a large cohort of patients who suffered an acute myocardial infarction with absolutely normal epicardial coronary arteries at the post-myocardial infarction coronary angiogram. The aetiological and prognostic factors in this population were also analysed. BACKGROUND: Few data exist concerning the outcome, and aetiological and prognostic factors, of patients with myocardial infarction and angiographically absolutely normal coronary arteries. METHODS: Ninety-one patients (34 females/57 males; mean age 50+/-13 years, range 24--78 years) admitted with an acute myocardial infarction had absolutely normal coronary arteries at the angiogram performed 6.2+/-4 days (range 1--15 days) after the myocardial infarction, defined by smooth contours and no focal reduction (NC). Of the 91 NC patients, 71 were evaluated prospectively, alongside a systematic search of all aetiological factors reported in the literature. The NC patients were matched for age, sex, and the same period of myocardial infarction onset with a group of 91 patients with coronary artery stenosis (>50% diameter stenosis) at the angiogram performed 7.3+/-4 days (range 1--15 days) after the myocardial infarction (SC). RESULTS: The percent of smokers was similar between the two groups; higher prevalence rates of coronary heart disease family history, obesity, hypertension, hypercholesterolaemia and diabetes mellitus were found in SC (P=0.043 to 0.0001). In NC, coronary spasm was found in 15.5%, congenital coagulation disorders in 12.8%, collagen tissue disorders in 2.2%, embolization in 2.2%, and oral contraceptive use in 1.1%. Left ventricular ejection fraction at hospital discharge was higher in NC (60%+/-13%) than in SC (55%+/-13%, P=0.04). The mean follow-up was 35 months (range 1--100 months). Kaplan-Meier event-free survival, with the combined end-point defined as death, reinfarction, heart failure and stroke was 75% in NC vs 50% in SC (P<0.0001). Survival rate was 94.5% in NC compared to 92% in SC (ns). Univariate predictors of events in NC were left ventricular ejection fraction (P=0.03), age (P=0.02), diabetes (P=0.01), and smoking (P=0.03). Using Cox multivariate analysis, independent predictors of long-term outcome in NC patients were left ventricular ejection fraction (P=0.003) and diabetes (P=0.004). CONCLUSION: Aetiological factors, predominantly coronary spasm and inherited coagulation disorder, can be detected in only one third of the patients with myocardial infarction and absolutely normal coronary angiograms despite a systematic search in a prospective population. Mortality rates are similar but morbidity is lower in myocardial infarction patients with absolutely normal coronary angiography compared with those with coronary artery stenosis. The only two independent factors predictive of poor outcome in myocardial infarction patients with normal coronary arteries are left ventricular function and diabetes.

Safe and effective placement of two bipolar silicone leads in the cephalic vein using a hydrophilic guidewire and a split introducer.

The cephalic vein (CV) is preferable to the subclavian vein for implanting permanent pacing leads because of fewer complications. Unfortunately, this access is unusable in a substantial number of patients. This prospective study evaluates a technique to increase CV access for the placement of two silicone bipolar leads used in DDD pulse generator implants. A standard cephalic cutdown was performed under local anesthesia and a hydrophilic guidewire (HGW) threaded in the CV. The first (ventricular) bipolar lead was then introduced and positioned. When possible, introduction of the second (atrial) lead followed the same direct access. A failed introduction led to a modified procedure (MP) relying on a "split" introducer (8-9 Fr Plastimed) advanced with a circular motion over the HGW, then removal of the dilator, removal of the HGW, insertion of the pacing lead into the sheath with placement in the right atrium, followed by sheath withdrawal. Over an 18-month period, 90 consecutive patients had DDD pacemakers implanted. The CV was accessible in 76 (84.5%) of 90 patients and the direct introduction of the ventricular lead was obtained in 74 (97.4%) of these. Atrialization proceeded as follows: direct access CV in 14 (18%) of 76 patients, MP access in 54 (71%) of 76 patients, and MP failure in 8 (11%) of 76 patients. Overall, this approach allowed cephalic dual insertion in 68 (89%) of 76 patients. In conclusion, the modified procedure presented in this study allows a dual catheterization with bipolar leads in 89% of patients when a CV is available. This significantly improves the success rate for dual bipolar lead implants in this configuration.

Use of the continuity equation for transesophageal Doppler assessment of severity of proximal left coronary artery stenosis: a quantitative coronary angiography validation study.

OBJECTIVES: We tested the value of transesophageal Doppler echocardiography (TEDE) for quantitating proximal left coronary artery (LCA) stenosis by using the continuity equation. BACKGROUND: The continuity equation applied to a stenosis states that the ratio of the time-velocity integral (TVI) of prestenotic to stenotic flow velocities is equal to the ratio of stenotic to prestenotic cross-sectional areas. TEDE allows the measurement of coronary blood flow velocities within the proximal part of the LCA. METHODS; Forty-one patients with a stenosis of the proximal or mid left anterior descending coronary artery or with a nonostial stenosis of the left main coronary artery were studied. Coronary flow velocities were recorded by TEDE guided by color flow imaging. Prestenotic velocities were recorded by pulsed Doppler echocardiography and transstenotic velocities were recorded by pulsed or high pulse repetition frequency or continuous wave Doppler echocardiography. The prestenotic and transstenotic diastolic TVIs were calculated and the TEDE-derived percent area stenosis was calculated as (1 - TVI ratio) x 100. Quantitative angiography lesion analysis was performed using a computer-assisted automated edge-detection system. RESULTS: TEDE recordings were successful in 35 of the 41 patients. A good linear correlation was found between TEDE and quantitative angiographically derived percent area stenosis (r = 0.89, p = 0.0001, SEE 5.7). However, TEDE measurements underestimated the actual percent area stenosis (slope of regression 0.54). A better agreement (slope 1.08) was obtained after dividing prestenotic velocity by 2 in the continuity equation, based on the assumption of a parabolic cross-sectional velocity profile in the prestenotic segment. CONCLUSIONS: TEDE may be used for quantitating stenosis of the proximal part of the LCA with the use of a modified continuity equation that takes into account the parabolic velocity profile in the normal prestenotic segment.

[Myocardial infarction following rapid perfusion of corticoids]. / Infarctus du myocarde au décours d'une perfusion rapide de corticoïdes.

The authors report the case of myocardial infarction occurring immediately after rapid intravenous infusion of a high dose of corticosteroids prescribed for a relapse of multiple sclerosis. Ventriculography confirmed the myocardial damage but the coronary arteries were normal. An aetiological investigation was negative. The authors review the cardiac secondary effects which may be very serious and even fatal. Coronary insufficiency is rare (only 3 previously published cases); it is therefore difficult to determine the prognosis. The possible mechanisms of infarction are discussed. Finally, the authors underline the importance of recording an ECG before treatment, of ECG monitoring during the infusion, and the need for repeating the recordings and of prolonging hospital admission when necessary.

[Left main coronary artery disease]. / La pathologie du tronc coronaire gauche.

There are many causes of left main coronary artery disease, the first of which is atherosclerosis. Other rarer causes may be observed, such as acute and chronic occlusions, spasm and primary and secondary dissection. The prevalence of stenosis of the left main coronary artery at coronary angiography is about 5%. The risk factors are the same as for coronary artery disease. The symptoms are angina, especially unstable angina. The diagnosis is suspected on the finding of an extremely positive exercise stress test, confirmed by coronary angiography. The results of the prospective large scale Veterans Administration trial showed surgery to be the treatment of choice with a 30 months survival of 80% in the surgical group compared with 64% in the medical group. The operative morbidity and mortality is less than 10% at present. Recent studies have reported a medium-term mortality of 4.3 to 10.25% with follow-up periods of 24 and 43 months respectively. The long-term survival and functional improvement are excellent, with values of nearly 80%. Chronic occlusion of the left main stem is rare, 0.01 to 0.7% in coronary angiographic studies. There is no difference in presentation, electrocardiographic or stress test features compared with other severe coronary artery disease. The diagnosis is angiographic and the treatment surgical because of the mediocre natural history with risks of sudden death and severe infarction. Acute occlusion of the left main coronary is rare for generally fatal. The mechanism is acute thrombosis and the clinical presentation is that of extensive infarction usually with cardiogenic shock.(ABSTRACT TRUNCATED AT 250 WORDS)

Myocardial infarction and nicotine patch: a contributing or causative factor?

A case of angina pectoris revealed by nicotine patch treatment is described in a patient who continued to smoke and subsequently suffered a myocardial infarction. The various side effects of nicotine and its derivatives are recalled. The action of nicotine on coronary vasomotricity and its mediators is discussed.

[A rare cause of loss of consciousness: mastocytosis. Apropos of 3 cases]. / Une cause rare de pertes de connaissance: la mastocytose. A propos de 3 cas.

The authors report three cases of syncope due to systemic mastocytosis. This is a rare cause of syncope but should be recalled in certain circumstances. In the light of these cases, the authors review the literature with respect to this unusual presentation. Syncope may occur at any age. Loss of consciousness may be more or less complete, brief or prolonged, isolated or recurrent and usually accompanied by prodromal symptoms. The least controversial physiopathogenic mechanism of these syncopes is intense vasoplegia induced by the release of vasoactive mediators, especially histamine. When there is a clinical suspicion of mastocytosis, even in the absence of skin changes, the diagnosis is confirmed by biopsy which shows abnormally high numbers of mastocytes irrespective of the organ biopsied. The treatment of acute forms with collapse is based on intravenous infusion of macromolecular fluids and injections of epinephrine. Prevention is by drugs which inhibit the synthesis of histamine, the degranulation of mastocytes and the production of prostaglandin D2.

[Painless infarction in antiphospholipid syndrome]. / Infarctus indolore au cours du syndrome des antiphospholipides.

The authors report a rare case of myocardial infarction secondary to coronary thromboses caused by the antiphospholipid syndrome. The relations between the cardiac pathology, especially the coronary disease, and antiphospholipid antibodies are recalled. The importance and methods of monitoring the anticoagulant therapy are emphasised.

[Left bundle-branch block and chest pain of simultaneous occurrence during exercise]. / Bloc de branche gauche et douleur thoracique d'apparition simultanée à l'effort.

The authors report a new case of left bundle branch block with pain during exercise, with arteriographically normal coronary arteries. Clinical findings and the course of the condition are reviewed. Pathophysiological mechanisms are discussed, with attribution of first place to an ischemic theory.

[Markers of hemostasis and myocardial infarction in persons under 40 years of age]. / Marqueurs de l'hémostase et infarctus du myocarde avant 40 ans.

Coronary disease before the age of 40 has special clinical and pathogenic features. The authors sought evidence of the existence of abnormalities of hemostasis markers in 39 patients aged under 40, several weeks after a myocardial infarction (MI). Blood samples were drawn a mean of 8 months after the MI. These laboratory studies included assay of C and S proteins, fibrinogen, clotting factors VII and VIII and antithrombin III, as well as detection of any possible circulating anticoagulant. Plasma levels of platelet factor 4 (PT4) and of beta-thromboglobulin (BTG) were measured in the same sample, enabling determination of the BTG/PF4 ratio. Only fibrinogen and plasma levels of platelet proteins were abnormal, revealing a significant difference between patients with multi-vessel disease and those with single vessel disease or free of severe angiographic lesions. Platelet activation appeared to persist some time after the MI, chiefly in patients with multi-vessel disease, and showing no relation to either age or treatment. Conclusions require prudence in view of difficulties in interpreting plasma assays of PF4 and of BTG.

[Localized type 2 dissection unrecognized by transesophageal echography. Apropos of a case]. / Dissections type 2 localisées méconnues par l'échographie transoesophagienne. A propos d'une observation.

The authors report a case of type 2 dissection, strictly confined to the terminal portion of the ascending aorta, not seen by transesophageal echocardiography because of the existence of a blind spot and responsible for a false negative. The role of TEE in the diagnostic approach to dissections is reviewed, as are its limitations, of which it is important to be aware because of the poor prognosis of pathology of this type.

[Cerebral abscess disclosing congenital heart disease]. / Abcès cérébral révélateur d'une cardiopathie congénitale.

Cerebrovascular accidents and brain abscesses are the most worrisome complications of cyanogenic cardiac lesions in infants and young children, but remain rare in the adult. The authors report the case of a brain abscess which led to the subsequent discovery of a congenital cardiac malformation consisting of a ventricular septal defect and moderate pulmonary valve stenosis. Complete correction of the cardiac lesions was carried out three months after neurosurgical treatment (needle biopsy/drainage).

[Spontaneous angina caused by spasm of the left coronary artery]. / Angor spontané par spasme du tronc coronaire gauche.

A 42 year old woman presented with a one year history of retrosternal chest pain and back pain on effort and at rest sometimes accompanied by minor syncopal attacks. Transient atrioventricular block was documented during one such episode associated with hypotension. Coronary angiography showed spontaneous spasm of the left main coronary artery with clinical symptoms but no electrocardiographic changes. The spasm was relieved by injection of SIN-1. The similarity between the previous clinical symptoms and those observed at coronary angiography was in favour of the diagnosis of spasm of the left main coronary artery without atherosclerotic coronary disease. Treatment with calcium atherosclerotic coronary disease. Treatment with calcium blockers and platelet antiaggregants led to total regression of her symptoms with a follow-up of 5 months.

[Spontaneous calcified coronary embolism and myocardial infarction. Apropos of a case]. / Embolie calcaire coronaire spontanée et infarctus du myocarde. A propos d'une observation.

The authors report a rare case of myocardial infarction due to calcific coronary embolisation in a patient with previously asymptomatic calcific aortic stenosis. The diagnosis was suggested by the finding of a lacunar image in the distal segment of the left anterior descending artery exactly corresponding to a punctiform mobile calcification visible before opacification of the coronary arteries. The clinical features of coronary embolism and in particular of calcific embolism are reviewed.

[Pheochromocytoma disclosed by isolated inflammatory syndrome]. / Phéochromocytome révélé par un syndrome inflammatoire isolé.

Among the atypical forms of phaeochromocytoma the isolated inflammatory form is rare and difficult to diagnose clinically. The authors report such a case, where computerized tomography and magnetic resonance imaging contributed enormously to the diagnosis.

[Torsades de pointes and prolongation of the duration of QT interval after injection of droperidol]. / Torsades de pointes et allongement de la durée de l'intervalle QT après injection de dropéridol.

Following a case of torsades de pointe (TDP) after the injection of droperidol (D), the authors studied the electrocardiographic variations caused by the drug. Fifty five unselected patients under the same conditions (general anesthesia) were given D (0.25 mg/kg IV). Significant prolongation of the QT interval was seen in 70% of cases by the end of the first minute. QT interval and the ratio of QTm (measured) over QTt increased from 387 +/- 34 ms to 423 +/- 37 ms (p less than 0.0001) and from 1.06 +/- 0.08 to 1.28 +/- 0.1 (p less than 0.001) respectively. These changes could favourise the onset of TDP. Although exceptional in terms of the extensive use of the neuroleptic in question, this possibility indicates the need for monitoring of the duration of QT before and during treatment with droperidol and for prescription of the drug to be avoided in circumstances known to be propitious to this arrhythmia (bradycardia, hypokalemia, anti-arrhythmic drugs).