Arrhythmogenic right ventricular dysplasia and sudden cardiac death in endurance athletes.

Arrhythmogenic right ventricular dysplasia (ARVD) is a cardiomyopathy with several time-dependent clinical presentations. The clinical characteristics depend on the penetration grade of the disease. There are two different histological patterns consisting of a lipomatous and a fibrolipomatous form. The presence of arrhythmias in the ARVD syndrome constitutes an important risk factor for sudden cardiac death in athletes. In this article, we describe two professional endurance athletes who died suddenly. One of these athletes had asymptomatic ARVD, the other had symptomatic polymorphic ventricular tachycardias. Both athletes showed fatty penetration of the disease in both the right and left ventricle; one of them also showed fatty involvement at the atrial level and in the other there were signs of myocarditis consistent with ARVD. In the last few years magnetic resonance imaging has become an important diagnostic tool in patients with ARVD.

Coronary arteriovenous fistulas: collective review and management of six new cases--changing etiology, presentation, and treatment strategy.

We considered it worthwhile to review the literature of the last decade (1985-1995) to answer the question whether the etiology and the clinical picture of coronary arteriovenous fistulas (CAVFs) have changed. Furthermore, new therapeutic modalities such as percutaneous transcatheter embolization have been developed. We tried to define the place of these techniques in the therapeutic arena. Clinical presentation and management of six patients with eight congenital CAVFs and 76 subjects with 96 congenital and acquire I CAVFs taken from a review of the recent literature are presented. Sixty-three review subjects (78%) were treated medically with one fatal case. Ligation of the fistula was achieved by surgical techniques in 10% of review subjects, while percutaneous transcatheter embolization (PTE) was performed in nine patients (12%). Percutaneous transcatheter embolization techniques are being increasingly used in the treatment of CAVFs. The etiology of CAVFs has a tendency to show alterations toward the acquired pathogenesis. In 64% of the review subjects the fistula was congenital in origin, and in 36% it had an acquired cause. Among the patients of the current review, the clinical presentations were 55% asymptomatic, 34% chest pain (anginal or atypical), and 13% congestive heart failure. The CAVFs of our six patients are all congenital in origin. In the current review, the clinical presentation showed a trend toward increasing chest complaints (34%) compared with the review (10%) published in the mid 1970s. This may be due to a higher mean age, and hence increased concurrent coronary artery disease due to aging compared with the review population of two decades ago.

Hydralazine-induced constrictive pericarditis.

A 59-year-old man was diagnosed as having constrictive pericarditis 17 months after a typical hydralazine-induced autoimmune syndrome. This late complication of hydralazine has been reported only once. Ten years later the patient was found to have anti-neutrophil cytoplasmic antibodies directed against myeloperoxidase.

Fractional flow reserve. A useful index to evaluate the influence of an epicardial coronary stenosis on myocardial blood flow.

BACKGROUND: Fractional flow reserve (FFR), defined as the ratio of maximum flow in the presence of a stenosis to normal maximum flow, is a lesion-specific index of stenosis severity that can be calculated by simultaneous measurement of mean arterial, distal coronary, and central venous pressure (Pa, Pd, and Pv, respectively), during pharmacological vasodilation. The aims of this study were to define ranges of FFR values, whether associated with inducible ischemia or not, and to investigate FFR in normal coronary arteries. METHODS AND RESULTS: In 60 patients accepted for percutaneous transluminal coronary angioplasty (PTCA) of single-vessel disease, with a positive exercise test (ET) < 24 hours before PTCA, FFR was determined during adenosine-induced hyperemia just before and 15 minutes after angioplasty. Pa was measured by the guiding catheter, Pd by an 0.018-in fiber-optic pressure-monitoring wire, and Pv, by a multipurpose catheter. The ET was repeated after 5 to 7 days, and only if this second ET had reverted to normal was the pre-PTCA value of FFR definitely considered to be associated with inducible ischemia and the post-PTCA value not. Myocardial FFR (FFRmyo) increased from 0.53 +/- 0.15 before PTCA to 0.88 +/- 0.07 after PTCA. Coronary FFR increased from 0.38 +/- 0.19 to 0.83 +/- 0.12. In all patients, values of FFRmyo definitely associated with ischemia were < or = 0.74, whereas all except two values not associated with inducible ischemia exceeded 0.74. Moreover, FFRmyo in 18 coronary arteries in 5 normal patients equaled 0.98 +/- 0.03. CONCLUSIONS: A value of FFRmyo of 0.74 reliably discriminates coronary stenosis, whether associated with inducible ischemia or not. Therefore, FFRmyo is a useful index to determine the functional significance of an epicardial coronary stenosis and may facilitate clinical decision making in patients with an equivocal coronary stenosis.

Quantification of recruitable coronary collateral blood flow in conscious humans and its potential to predict future ischemic events.

OBJECTIVES: The present study was designed to evaluate the applicability of a pressure-flow equation for quantitative calculation of recruitable collateral blood flow at coronary artery occlusion in conscious patients and to investigate the value of that index to predict future ischemic events. BACKGROUND: Recent experimental studies have indicated that recruitable collateral blood flow at coronary artery occlusion can be expressed as a fraction of normal maximal myocardial blood flow by simultaneous recordings of mean arterial, coronary wedge and central venous pressures, respectively. This index is called the pressure-derived fractional collateral flow and is independent of hemodynamic loading conditions. METHODS: In 120 patients undergoing elective coronary angioplasty, mean arterial, coronary wedge and central venous pressures were measured at balloon inflations of 2 min. All patients had a recent exercise electrocardiogram (ECG) with positive findings showing clearly distinguishable, reversible ECG abnormalities, enabling recognition of ischemia at balloon inflation. Fractional collateral blood flow at angioplasty was calculated by coronary wedge pressure minus central venous pressure divided by mean arterial pressure minus central venous pressure and correlated to the presence or absence of ischemia at balloon inflation. Ischemic events were monitored during a follow-up period of 6 to 22 months. RESULTS: In 90 of the 120 patients, ischemia was present at balloon inflation, and in 82 of these patients, fractional collateral blood flow was < or = 23%. By contrast, in 29 patients, no ischemia was present, and fractional collateral blood flow was > 24% in all 29. During the follow-up period, 16 patients had an ischemic event. Fifteen of these 16 patients were in the group with insufficient collateral flow (p < 0.05). CONCLUSIONS: To our knowledge, this study presents the first method for quantitative assessment of recruitable collateral blood flow in humans in the catheterization laboratory. Sufficient and insufficient collateral circulation can be reliably distinguished by this method. Use of this method can also help to provide more insight into the extent and behavior of the collateral circulation for investigational purposes and may have potential clinical implications.

Coronary angiographic morphology of congenital coronary arteriovenous fistulas in adults: report of four new cases and review of angiograms of fifteen reported cases.

The coronary angiographic features of four new cases of congenital coronary arteriovenous fistulas (CAVFs) are described, and the angiograms of 15 reported cases are reviewed. The morphologic appearance of CAVFs varied from a small discrete single channel to a highly complex plexiform network with a maze of fine vessels. The majority of CAVFs in our series were composed of a single channel. Aneurysmal formation was present in 26% (6/23). Aneurysmal formation involved only the pathway and/or the termination, but never originated from the beginning of the CAVFs.

P wave oversensing in a unipolar VVI pacemaker.

A 45-year-old male had a VVI pacemaker implanted 20 years ago because of complete heart block. Because of perforation of the lead the pulse generator was removed after 4 weeks and a second lead was implanted from the contralateral side. Recently, the patient presented with symptoms of lightheadedness and syncope associated with prolonged pauses in the electrocardiogram. From the ECG, the ECG interpretation channel, and intracardiac electrogram telemetry, it was concluded that the VVI pacemaker was inhibited by P waves. The most likely explanation for this phenomenon was an insulation defect in the functioning lead caused by friction with the abandoned lead at the level of the high right atrium.

Upper rate pacing after radiofrequency catheter ablation in a minute ventilation rate adaptive DDD pacemaker.

A 58-year-old man with an implanted minute ventilation rate adaptive DDD pacemaker underwent RF ablation of the AV junction because of symptomatic supraventricular tachyarrhythmias. Immediately after ablation, while the pacemaker was programmed in the DDDR mode, AV sequential pacing at upper rate was observed. After programming the pacing system to the DDD mode and repeated ablation, no abnormalities were observed. It was concluded that AV sequential upper rate pacing was caused by false interpretation of the RF current by the sensor measuring transthoracic impedance as an indicator for minute ventilation.

Retrieval of undeployed stents from the right coronary artery: report of two cases.

Two patients are described in whom an undeployed stent (1 Wiktor and 1 Palmaz-Schatz) was retained in the proximal segment of the right coronary artery during coronary angioplasty. In both cases the stent was caught by a technique using a second guidewire. The stent was removed in the first patient during bypass surgery; in the second patient it was removed from the femoral sheath.

Adapter failure as a cause of pacemaker malfunction.

Two patients who had recently undergone pulse generator replacement in which an adapter had been used to connect a preexisting lead to a VS1 and IS1 3.2-mm connector presented with noncapture. The adapter set-screw was found to be protruding from the insulation sleeve to short-circuit with the pulse generator can. During episodes of noncapture the telementered impedance was < 100 ohms.

Incidence of atrioventricular block and chronic atrial flutter/fibrillation after implantation of atrial pacemakers; follow-up of more than ten years.

The incidence of atrioventricular (AV) block and chronic atrial flutter/fibrillation was determined in 41 patients, mean age 62.2 years (22 to 88 years) who received atrial pacemakers before October 1980. The mean follow-up period was 12.3 years, range 11-14.4 years. Twenty-five patients suffered from bradycardia-tachycardia syndrome, 13 symptomatic bradycardia, and 3 bradycardia related ventricular tachycardia. At follow-up: 18 patients (44%) had permanent I-AV block; 11 patients had II-AV block, 9 patients (22%) transient Wenckebach block and 2 patients (5%) transient Mobitz block, all asymptomatic. The cumulative incidence of III-AV block was 1 (2.5%). Chronic atrial flutter/fibrillation occurred in 6 patients (15%), 5 were not pacemaker-dependent; 1 received a ventricular pacemaker. Seventeen patients died after a mean of 7 years (0.6-12.2 years). Cumulative survival rate of 58% for 14.4 years, did not differ from a matched cohort of the normal population. There were no pacemaker related deaths. We conclude that long-term atrial pacing was safe and effective. The incidence of III-AV block and chronic atrial flutter/fibrillation was low.

Shearing of the plastic coating of a hydrophilic guide wire in a right femoropopliteal bypass graft: removal from the contralateral side.

The plastic coating of a hydrophilic guide wire tore off during introduction through a beveled single wall arterial entry needle in a 75 year old male. The sheared piece of coating got stuck in his femoropopliteal bypass. It was removed by means of a modified arterial filter set from the contralateral side. The technique of its removal is described.

Apparent P wave undersensing in a DDD pacemaker post exercise.

Wenckebach behavior of DDD pacemakers occurring when the P-P interval varies between the programmed upper rate interval and the total atrial refractory period is symmetrical in a sense that the pacemaker response during atrial rate acceleration is similar to the pacemaker response during atrial rate deceleration. This phenomenon can be observed in all patients with persistent AV block in whom a DDD pacemaker is implanted, during exercise testing when the spontaneous atrial rate exceeds the selected upper rate, i.e., the programmed upper rate interval. However, this phenomenon will not be observed in all patients with intermittent intact AV conduction during exercise. In this case report we describe a patient who showed an asymmetrical response during a bicycle exercise test. There was 1:1 atrial sensing ventricular pacing until the atrial rate exceeded the upper rate of 140 ppm, while atrial sensing was restored during recovery when the conducted sinus rhythm had decreased to 105 beats/min.

Optimized hemodynamics by implantation of a dual chamber pacemaker after heterotopic cardiac transplantation.

A patient who underwent prior heterotopic cardiac transplantation had persistent complaints of dyspnea, palpitations, and fatigue in spite of normal pump function of the donor heart. Repeated Holter monitoring excluded paroxysmal arrhythmias. It was thought that synchronization of both heart rates might alleviate his symptoms. The intrinsic heart rate of the donor heart was 90 beats/min, the recipient heart was 60 beats/min with acceleration up to 130 beats/min on exercise. A DDD pacemaker was implanted, the atrial lead was positioned in the right ventricule of the donor heart and the ventricular lead in the atrium of the recipient heart. Search for an optimal AV interval was evaluated by echo-Doppler and intraarterial pressure recordings. By increasing the AV interval from 125 to 300 msec, the maximum aortic flow velocity of the recipient heart increased from 1.0 to 1.2 m/sec. Left ventricular end-diastolic diameter remained unchanged, left ventricular end-systolic diameter decreased from 52 to 48 mm. Wall motion of the recipient left ventricle improved. At an AV interval of 125 msec there was alternate systolic contraction of both hearts, resulting in arterial pressure waves at a rate of 180/min. This did not relieve his symptoms and he complained further of headaches. At an AV interval of 300 msec contraction of the recipient heart just preceded that of the donor heart, resulting in arterial pressure waves at a rate of 90/min, normalization of the wave form, relief of symptoms, and improvement of exercise tolerance.

Fusion or confusion on Holter recording.

Holter recording of a patient with an implanted dual chamber rate responsive pacemaker revealed an electrocardiogram, where ventricular depolarization seemed to be initiated by the atrial stimulus. In a second patient with a VVI pacemaker, Holter recording showed delay of the pacemaker impulse that was registered after the onset of ventricular depolarization. Misalignment in one of the recorder heads of the display system was responsible for this phenomenon, which in case of dual chamber pacing could have been easily misinterpreted as pacemaker malfunction.

Acute myocardial ischaemia and cardiogenic shock after percutaneous transluminal coronary angioplasty; risk factors for and results of emergency coronary bypass.

Between 1 September, 1980 and 1 January, 1989, 4142 patients underwent percutaneous transluminal coronary angioplasty (PTCA). We retrospectively studied the 155 [3.7%; 119 males, mean age 53.4 years, (range 33-78 years) and 36 females, mean age 59.6 years (range 40-74 years)] who required urgent coronary artery bypass grafting (CABG) (Group I) and a select control group of 155 patients, in whom PTCA was performed without complications (Group II). Before PTCA, 14 Group I and 42 Group II patients had angina Class II, and 78 Group I and 49 Group II patients had angina class IV (chi 2-test, P less than 0.05). There were 445 complications in the 155 group I patients: 303 (68%) early (during PTCA) and 141 (32%) late (within 24 h). On arrival in the operating room 126 patients were stable; five were in cardiac arrest and 19 in cardiogenic shock (AS-group; 24 patients). In the AS-group and control group, respectively, angina Class II occurred in 2/24 (8.3%) and 42/155 (27.1%) patients, angina Class IV in 14/24 (58.3%) and 49/155 (31.6%) (P less than 0.05), single-vessel disease in 8/24 (33.3%) and 85/155 (54.8%), triple-vessel disease in 7/24 (29.2%) and 23/155 (14.9%) (P less than 0.05); elective PTCA in 11/24 (45.8%) and 92/155 (59.4%), urgent PTCA in 12/24 (50%) and 48/155 (30.9%) (P less than 0.05), PTCA of the left anterior descending artery (LAD) in 18/24 (75%) and 86/166 (51.8%), PTCA of the right coronary artery in 2/24 (8.3%) and 47/166 (28.3%) (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Catheter reperfusion for failed emergency coronary angioplasty without subsequent bypass surgery.

A transluminal intracoronary reperfusion catheter was used in eight patients, seven with acute myocardial infarction and one with unstable angina after failed emergency coronary angioplasty. After placement of the reperfusion catheter across the occlusion, symptoms of ischemia resolved in each patient. Chest pain recurred 3 hr later in a single patient who underwent successful repeat angioplasty. The catheter was withdrawn within 6 hr after introduction. Control coronary angiography showed a patent vessel in all but one. Repeat angioplasty or bypass surgery was unnecessary. During 1 year mean follow-up time all patients remained free of symptoms. The reperfusion catheter is a safe and effective means of perfusing a coronary artery after failure of thrombolytic therapy and coronary angioplasty in cases where emergency bypass surgery is not performed because operative morbidity is expected to outweigh the benefit of myocardial salvage, or when it cannot be immediately organized.

Changes in morphology of the paced QRS complex related to pacemaker output.

The influence of pacemaker output on the morphology of the paced QRS complex was studied from standard lead electrocardiograms in 69 patients with bipolar pacemakers. In 40 of the 69 patients (58%), there was a significant (P less than 0.001) change in electrical axis, from -75 degrees at the low output setting (2.7 V, 0.15 msec) to -67 degrees at the high output setting (8.1 V, 2.29 msec). In 30 patients, these changes were also associated with changes in the QRS morphology and in the T-wave. This phenomenon may be explained by additional stimulation from the proximal electrode at high output, thus altering the pattern of depolarization.

Unstable angina, myocardial infarction and sudden death after an exercise stress test.

We performed coronary angiography within 95 minutes of the onset of symptoms in seven patients with an acute coronary event after an exercise stress test. The test was normal in six patients. Previous angiography in four patients revealed no evident or moderate obstructive coronary arterial disease. After the test, unstable angina developed in two patients, acute myocardial infarction in four and ventricular fibrillation in one, who was successfully resuscitated. At acute angiography the coronary artery involved was occluded in four and sub-totally obstructed in three. In three cases, coronary occlusion was due to thrombosis, vasospasm, or both. In six vessels there was an eccentric lesion, which is consistent with a ruptured plaque. These findings show that physical exercise can unexpectedly provoke an acute coronary event with sub-total or total occlusion of a previous angiographically normal or moderately obstructed coronary artery. The mechanism is probably related to exercise-induced plaque rupture which can produce coronary (sub)occlusion by coronary thrombosis, spasm, or both.

Myocardial infarction and sudden death after sport: acute coronary angiographic findings.

Thirteen patients, seven with acute myocardial infarction and six survivors of sudden death after sport, underwent coronary angiography within a mean of 104 min after the onset of symptoms. The admission electrocardiogram showed transmural myocardial ischemia in all patients. The ischemia-related vessel was occluded in all cases of sudden death and in three cases of acute myocardial infarction. Reperfusion was achieved in eight vessels: after intracoronary streptokinase in three, after intracoronary nitroglycerin in three, and mechanically in two. Coronary spasm was demonstrated in three vessels, and coronary thrombi, in four. The coronary lesion was described as either concentric in two or eccentric with irregular borders in eight. There was a high incidence of eccentric lesions consistent with ruptured plaques. The acute coronary angiographic findings of acute myocardial infarction and sudden death after sport are similar. Physical exercise can provoke myocardial infarction and sudden death probably by inducing plaque rupture that can evoke coronary spasm, thrombosis, or both.