Pulse Deficit Research Articles

Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) in a Boxer

ABSTRAST: A 3-year-old boxer bitch was evaluated for syncope and exercise intolerance. Physical examination revealed tachypnea, tachyarrhythmia and pulse deficit. Echocardiography demonstrated right atrial dilatation, thinning and hypokinesis of the right ventricular wall and normal contractility of the left ventricle. Three months after the first onset of clinical symptoms, the dog developed signs of congestive right heart failure despite treatment, and euthanasia was performed because of refractory ascites. The diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) was reached based of the clinical evolution of rapid progressive right ventricular heart failure and the particular form of isolated right atrial and right ventricular alterations without any echographic abnormalities of the pulmonic and tricuspid valves. Definitive confirmation was made by necropsy. In contrast to boxer type dilated cardiomyopathy (BDCM), dilatation occurred primary on the right atrium and ventricle and the right ventricular wall was thinner in subtricuspidal, apical and infundibular locations, similar to the "triangle of dysplasia" of human patient with ARVC. Histological lesions showed myocyte atrophy and replacement with adipose and fibrous tissue extended from the epicardium toward the endocardium in the right ventricle (RV) and right atrium (RA). In contrast to BDCM, where the lesions are multifocal, they take here the form of waves, with a large base against the epicardium and a spike towards the endocardium, known as lesions with a wave-front pattern, which are typical of ARVC. This report with supraventricular arrhythmias and echographic location in the RA and RV supports the hypothesis that ARVC is a progressive disease which may also have left ventricular free wall involvement if the patient lives long enough.

Decrements in per pulse release of norepinephrine, antagonist potentiation of release and presynaptic receptor theory

In recent decades the theory that amine transmitter release at nerve terminals is routinely regulated through negative feedback systems sensing and responding to the instantaneous perineuronal concentration of previously liberated transmitter has assumed pre-eminence. However, observations indicate a major drop off in per pulse transmitter release when only two or four stimulation pulses are administered, reflecting the unexpectedly prompt operation of feedback inhibition. We explored this quandary in our understanding of control of transmitter release by axonal depolarization versus terminal feedback using isotopic norepinephrine and in vitro slices of rabbit hippocampus. A technique of continuous collection of superfusate over a 30 min cycle of stimulation utilizing a wide range of intervals between individual stimulation pulses was used. Following simulation with single pulses even 60 s apart or pseudo one pulses 150 s apart a marked decline in per pulse release was noted. The deficits in per pulse release were not related to the number of pulse delivered at any time over the course of a 30 min stimulation period. The pulse decrements were independent of the activity of neuronal uptake and of superfusion flow rate or even individual pulse duration and frequency. Presynaptic receptor antagonists, potentiated efflux near maximally with the second of only two pulses. Potentiations were independent of pulse number, pulse duration, or frequency. No linkage between perineuronal transmitter concentrations and the antagonist potentiation of release was found. However, the decrements in per pulse release with multiple pulses and the potentiation by alpha presynaptic antagonists occurred under the same test conditions. We conclude that the pulse deficit can be looked at as largely attributable to an enhanced efflux with delivery of the first pulse in a train of pulses, rather then to a pattern of progressively declining efflux linked to increasing extracellular transmitter levels as frequency and pulse number increase.

Duplex Evaluation of Trauma from Gunshot Wounds

Introduction Diagnosis and repair of arterial injury from penetrating trauma is critical because the lack of intervention can result in limb loss or death. Patients that have conspicuous arterial injuries can be explored and repaired in the operating room with or without preoperative diagnostic imaging. Patients without definite clinical evidence of vascular injury (i.e., hematoma, pulsatile mass, bruit, or pulse deficit) generally undergo angiography because of proximity of injury. Arteriography is an expensive and invasive procedure for patients; it carries some discomfort and has potential complications associated with its use. In our experience, ankle/brachial index (ABI) alone has not been a dependable study to rule out significant arterial injury of extremities. Color flow duplex imaging is a painless procedure, has no risk to the patient, is not as expensive as arteriography and is readily available in most institutions. We present two patients who had normal pulses and ABIs after gunshot wounds to extremities. Both patients had significant arterial injury detected by color flow duplex imaging as the initial diagnostic modality and subsequently proceeded on to arteriography based on the findings of the duplex studies. Conclusions The findings of the duplex imaging were in direct correlation with arteriography. These two cases demonstrate the sensitivity of color flow duplex ultrasonography to detect extremity arterial injuries in a community hospital.

Discussion: Session 3—Dissection

Discussion: Session 3—Dissection

Acute type A aortic dissection in the elderly: clinical characteristics, management, and outcomes in the current era

ObjectivesWe sought to evaluate the clinical characteristics, management, and outcomes of elderly patients with acute type A aortic dissection. BackgroundFew data exist on the clinical manifestations and outcomes of acute type A aortic dissection in an elderly patient cohort. MethodsWe categorized 550 patients with type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection into two age strata (<70 and ≥70 years) and compared their clinical features, management, and in-hospital events. ResultsThirty-two percent of patients with type A dissection were aged ≥70 years. Marfan syndrome was exclusively associated with dissection in the young, whereas hypertension, atherosclerosis and iatrogenic dissection predominated in older patients. Typical symptoms (abrupt onset of chest or back pain) and signs (aortic regurgitation murmur or pulse deficits) of dissection were less common among the elderly. Fewer elderly patients were managed surgically than younger patients (64% vs. 86%, p < 0.0001). Hypotension occurred more frequently (46% vs. 32%, p = 0.002) and focal neurologic deficits less frequently (18% vs. 26%, p = 0.04) among the elderly. In-hospital mortality was higher among older patients (43% vs. 28%, p = 0.0006). Logistic regression analysis identified age ≥70 years as an independent predictor of hospital death for acute type A aortic dissection (odds ratio 1.7, 95% confidence interval 1.1–2.8; p = 0.03). ConclusionsOur study shows significant differences between older (age ≥70 years) and younger (age <70 years) patients with acute type A aortic dissection in their clinical characteristics, management, and hospital outcomes. Future research should evaluate strategies to improve outcomes in this high-risk elderly cohort.

Evaluation of patients with peripheral vascular disease

Approximately 10% of people age >55 years have asymptomatic peripheral atherosclerotic disease (PAD), 5% have intermittent claudication (IC, the cardinal symptom), and 1% critical leg ischemia (rest pain or gangrene). In patients with IC, worsening occurs in ∼16%, bypass surgery is required in ∼7%, and amputation in ∼4%. Disease progresses more frequently in diabetics and in tobacco smokers. Patients with PAD suffer increased cardiovascular morbidity related mainly to coronary artery disease with a mortality rate of approximately 30% after 5 years. Compared to patients without PAD, the relative risk of coronary death is approximately 6.6, overall cardiovascular mortality 5.9, and all-cause mortality 3.1. Pain at rest or ischemic gangrene indicates severe, often multilevel arterial occlusive disease and calls for aggressive management, which usually includes angiography and revascularization by percutaneous angioplasty or surgery. Critical limb ischemia results in some 150,000 amputations annually in the U.S., with perioperative mortality rates of 5-10% for below-knee and up to 50% for above-knee amputation because of comorbidities. Physical findings include trophic signs of ischemia, vascular bruits and peripheral pulse deficits. Ischemic ulcers usually involve the tips of the toes or the heel of the foot, and are typically painful on elevation and most bothersome at night. Ancillary diagnostic modalities begin with the ankle/arm systolic pressure index (ABI); a value <0.90 indicates PAD with significant prognostic implications. More precise assessment in the noninvasive vascular laboratory may involve a combination of segmental limb pressure measurements and pulse volume waveform recording, which is over 90% accurate for predicting the level and extent of PAD. Exercise testing enhances the value of these observations. Magnetic resonance imaging methods are emerging to characterize the arterial wall and atherosclerotic lesions. The diagnosis of PAD does not generally require invasive techniques, and most patients with IC do not need contrast angiography. Angiography is indicated for mapping of the extent and location of arterial pathology prior to revascularization.

Does this patient have an acute thoracic aortic dissection?

The diagnosis of acute thoracic aortic dissection is difficult to make and often missed. To review the accuracy of clinical history taking, physical examination, and plain chest radiograph in the diagnosis of acute thoracic aortic dissection. A comprehensive review of the English-language literature was conducted using MEDLINE for the years 1966 through 2000. Additional sources were identified from the references of retrieved articles. The search revealed 274 potential sources, which were reviewed for pertinence and quality. Articles included were original investigations describing the clinical findings for 18 or more consecutive patients with confirmed thoracic aortic dissection. Twenty-one studies were identified that met selection criteria. Critical appraisal and data extraction were performed by the author. Most patients with thoracic aortic dissection have severe pain (pooled sensitivity, 90%) of sudden onset (sensitivity, 84%). The absence of sudden pain onset lowers the likelihood of dissection (negative likelihood ratio [LR], 0.3; 95% confidence interval [CI], 0.2-0.5). On examination, 49% of patients have an elevated blood pressure, 28% have a diastolic murmur, 31% have pulse deficits or blood pressure differentials, and 17% have focal neurological deficits. Presence of a diastolic murmur does little to change the pretest probability of dissection (positive LR, 1.4; 95% CI, 1.0-2.0), whereas pulse or blood pressure differentials and neurological deficits increase the likelihood of disease (positive LRs, 5.7 and 6.6-33.0, respectively). The plain chest radiograph results are usually abnormal (sensitivity, 90%); hence, the presence of a normal aorta and mediastinum decreases the probability of dissection (negative LR, 0.3; 95% CI, 0.2-0.4). Combinations of findings increase the likelihood of disease. The presence of pulse deficits or focal neurological deficits increases the likelihood of an acute thoracic aortic dissection in the appropriate clinical setting. Conversely, a completely normal chest radiograph result or the absence of pain of sudden onset lowers the likelihood. Overall, however, the clinical examination is insufficiently sensitive to rule out aortic dissection given the high morbidity of missed diagnosis.

Beware of the Migrating Chest Pain and Widened Mediastinum: Case Series on Aortic Dissection

Objective Aortic dissection is not a rare life-threatening emergency. Undiagnosed and untreated aortic dissection is associated with a high mortality. A review of cases in the hospital may provide a baseline picture to guide clinical decisions. Design Retrospective case review for a period of 3 years and 4 months. Setting District general hospital near the Hong Kong – Shenzhen ‘border’ with 24-hour Accident &amp; Emergency service but without cardiothoracic surgical capability. Population All cases coded as ‘aortic dissection’ in the computerized ‘Clinical Management System’ of the hospital. Main outcome measures Date, sex, age, history of hypertension, presenting symptoms, pulse deficit, chest X-ray findings, pericardial effusion, A&amp;E diagnosis, type of dissection and patient outcome. Results From August 1998 to November 2001, 26 cases of aortic dissection were identified. There were 19 males and 7 females. Age range was 26 to 90 years (mean 65.04 ± SD 15.04, median 66.50, mode 65). In the plain chest X-rays, widened superior mediastinum (&gt;8 cm) was present in 19 patients (73.1%) and pleural effusion in three (11.5%). Pericardial effusion was found in six patients (23.1%). As regard to outcome, 11 were discharged home (42.3%), 14 were transferred to cardiothoracic surgical unit (where two subsequently died) and one died in the hospital. Conclusion The prevalence of aortic dissection may be more common than is generally appreciated by emergency physicians. Owing to its variable clinical presentations mimicking other diseases, the diagnosis of aortic dissection is easily missed. Higher clinical vigilance should be exercised for this potentially deadly condition.

Usefulness of pulse deficit to predict in-hospital complications and mortality in patients with acute type A aortic dissection

Vascular compromise seen with pulse deficits is common in patients with type A dissection. However, patient characteristics and in-hospital outcomes associated with pulse deficits have not been evaluated. Accordingly, we studied 513 patients (mean age 62 ± 14 years, 65% men) with acute type A aortic dissection enrolled in the International Registry of Acute Aortic Dissection. Pulse deficits, defined as decreased or absent carotid or peripheral pulses as noted by clinicians and later confirmed by diagnostic imaging, at surgery or at autopsy were noted in 154 patients (30%). Age <70 years, male gender, neurologic deficit(s), altered mental status, and hypotension, shock, or tamponade on admission were all significantly higher in patients with than without pulse deficits. The etiology of aortic dissection, clinical symptoms, and imaging findings were similar in the 2 groups. In-hospital complications (hypotension, coma, renal failure, and limb ischemia) and mortality (41% vs 25%, p = 0.0002) were significantly higher in patients with pulse deficit. Cox proportional-hazards regression analysis identified pulse deficit as an independent predictor of 5-day in-hospital mortality (risk ratio 2.73, 95% confidence interval 1.7 to 4.4; p <0.0001). Further, overall mortality rates increased with an increasing number of pulse deficits (p for trend <0.0001). Pulse deficits are common findings in patients with type A aortic dissection and identify those at high risk of in-hospital adverse events. This simple clinical sign should direct physicians to consider a diagnosis of aortic dissection in patients with acute chest pain, and should help identify a subgroup of patients who would benefit from more aggressive strategies.

ECG interpretation in small animals

THIS article, the first of three aimed at assisting those in practice in interpreting electrocardiograms (ECGs), discusses the electrical activity of the heart and how this relates to the complexes...

Elimination of Pulse Deficit During Atrial Fibrillation by Left Vagal Stimulation

Six anesthetized dogs (17–25 kg) were used to test the hypotheses that low-frequency, left-vagal stimulation can be used to reduce or eliminate pulse deficit during atrial fibrillation. Atrial fibrillation was induced and sustained by rapid electrical stimulation of the right atrium using a J-lead placed in the right atrial appendage. A bipolar sleeve electrode was placed around the left vagus nerve in the cervical region and low-frequency 1-ms rectangular current pulses were applied. Pulse deficit was completely eliminated in 28 of the 29 trials and was reduced in all 29. Additionally, an increase in mean blood pressure was observed at the commencement of vagal stimulation and a decrease in mean blood pressure was observed after cessation of left vagal stimulation, when the pulse deficit reappeared. We conclude that controlled low-frequency left vagal stimulation is an effective way to eliminate the pulse deficit in atrial fibrillation.

Continued experience with physical examination alone for evaluation and management of penetrating zone 2 neck injuries: Results of 145 cases

Purpose: Our preliminary experience with physical examination alone in the evaluation of penetrating zone 2 neck injuries for vascular trauma was previously reported in 28 patients over a 2-year period (1991-1993). The purpose of the current study was to examine the results of this approach in a much larger group of patients over an 8-year period. Methods: The medical records for all patients admitted to our level I trauma center (all of them entered into our prospective protocol) between December 1991 and April 1999 with penetrating zone 2 neck trauma were reviewed for their initial presentation and any documented vascular injury. Results: A total of 145 patients made up the study group; in 30 of these patients, the penetrating trajectory also traversed zone 1 or 3. Thirty-one patients (21%) had hard signs of vascular injury (active bleeding, expanding hematoma, bruit/thrill, pulse deficit, central neurologic deficit) and were taken immediately to the operating room; 28 (90%) of these 30 patients had either major arterial or venous injuries requiring operative repair (the false-positive rate for physical examination thus being 10%). Of the 114 patients with no hard signs, 23 underwent arteriography because of proximity of the injury to the vertebral arteries or because the trajectory included another zone. Of these 23 arteriograms, three showed abnormalities, but only one required operative repair. This case had no complications relating to the initial delay. The remaining 91 patients with no hard signs were observed without imaging or surgery for a minimum of 23 hours, and none had any evidence of vascular injury during hospitalization or during the initial 2-week follow-up period (1/114; false-negative rate for physical examination, 0.9%). Conclusions: This series confirms the earlier report indicating that patients with zone 2 penetrating neck wounds can be safely and accurately evaluated by physical examination alone to confirm or exclude vascular injury. The missed-injury rate is 0.7% (1/145) with this approach, which is comparable to arteriography in accuracy but less costly and noninvasive. Long-term follow-up is needed to confirm this management option. (J Vasc Surg 2000;32:483-9.)

The International Registry of Acute Aortic Dissection (IRAD)

Acute aortic dissection is a life-threatening medical emergency associated with high rates of morbidity and mortality. Data are limited regarding the effect of recent imaging and therapeutic advances on patient care and outcomes in this setting. To assess the presentation, management, and outcomes of acute aortic dissection. Case series with patients enrolled between January 1996 and December 1998. Data were collected at presentation and by physician review of hospital records. The International Registry of Acute Aortic Dissection, consisting of 12 international referral centers. A total of 464 patients (mean age, 63 years; 65.3% male), 62.3% of whom had type A dissection. Presenting history, physical findings, management, and mortality, as assessed by history and physician review of hospital records. While sudden onset of severe sharp pain was the single most common presenting complaint, the clinical presentation was diverse. Classic physical findings such as aortic regurgitation and pulse deficit were noted in only 31.6% and 15.1% of patients, respectively, and initial chest radiograph and electrocardiogram were frequently not helpful (no abnormalities were noted in 12.4% and 31.3% of patients, respectively). Computed tomography was the initial imaging modality used in 61.1%. Overall in-hospital mortality was 27.4%. Mortality of patients with type A dissection managed surgically was 26%; among those not receiving surgery (typically because of advanced age and comorbidity), mortality was 58%. Mortality of patients with type B dissection treated medically was 10.7%. Surgery was performed in 20% of patients with type B dissection; mortality in this group was 31.4%. Acute aortic dissection presents with a wide range of manifestations, and classic findings are often absent. A high clinical index of suspicion is necessary. Despite recent advances, in-hospital mortality rates remain high. Our data support the need for continued improvement in prevention, diagnosis, and management of acute aortic dissection.

The Utility of Physical Examination in Proximity Penetrating Extremity Trauma

This study assessed the efficacy of physical examination as a screening modality for the diagnosis of surgically significant arterial injury in proximity penetrating extremity trauma (PPET). All cases of PPET were assessed and admitted per established protocol over a 30-month period from January 1, 1993, to June 30, 1995. No patients were excluded if other body regions were also injured. Landmarks defining upper extremity injuries were the deltopectoral groove to the wrist and for lower extremities from the inguinal ligament to the ankle. Patients admitted with PPET fell into one of three categories: 1) no hard signs of vascular injury present-admitted for 24-hour observation; 2) presence of at least one hard sign of vascular injury-taken immediately to the operating room; 3) positive sign of arterial injury that requires angiography (i.e., diminished but appreciable pulse by physical examination or doppler, large nonexpanding hematoma, bilateral pulse deficit, no appreciable pulse with unreconstructable trajectory). Four hundred six patients with 489 injured extremities secondary to PPET were admitted over a 30-month period. Sixty-two extremities suffered multiple injuries. Of the extremities injured, 83 per cent were secondary to gunshot wounds, 12 per cent were attributed to stabs/lacerations, and 5 per cent were due to shotgun injuries. Four hundred twenty-one extremities with PPET fell into Group 1. There were four missed injuries (specificity, 99%) in this group (one ulnar artery, one radial artery, one posterior tibial artery, and one anterior tibial artery). Two of these injuries were considered surgically significant. None of the patients suffered limb or functional loss as a consequence of their missed arterial injury. Thirty-nine extremities were entered into Group 2, with two patients found to have no arterial injury. Twenty-nine extremities were placed into Group 3 with 10 (35%) found to have surgically significant injury on angiogram. The overall sensitivity and specificity for physical examination was 92 per cent and 95 per cent, respectively, for surgically significant injury. Physical examination is a highly sensitive and specific screening modality for the identification of surgically significant arterial injury in PPET. Patients who present with diminished, but appreciable, pulses by physical examination or doppler, large nonexpanding hematomas as the only sign, bilateral pulse deficits and nonappreciable pulses with unreconstructable trajectory benefit from further investigation with angiography.

Hemodynamic Change during Premature Ventricular Contraction with Different Sites of Origin and Coupling Intervals in Dogs

Background:In general, pulse pressure of a VPC depends on its prematurity and the site of origin. The pulse pressure of a VPC with a short coupling interval or originating from the left ventricle tends to be smaller. However, the hemodynamic change of a VPC originating from the right ventricular outflow tract (RVOT is not well elucidated. In addition to their prematurity and the site of the origin of VPCs, the left ventricular filling profile (Ei/Ai ratio during preceding control beats may affect the occurrence of a subsequent pulse deficit. The purpose of this study is to evaluate the hemodynamic change of different coupling intervals of VPCs originating from the RVOT. Furthermore, this study evaluates whether the left ventricular filling profile during preceding control beats significantly affects the occurrence of pulse deficits by VPCs. Methods:In 12 open-chest dogs anesthetized with α-chloralose, sinus node crushing was done, and then a single bipolar ventricular pacing using sutured epicardial electrodes was done at 3 different sites;left ventricular apex (LVA, right ventricular apex (RVA, RVOT. At each site, a single bipolar pacing was done with a different coupling interval;500 msec, 450 msec, 400 msec, 350 msec, 300 msec. During the production of VPCs, the mitral filling flow velocity and aortic TVI (time-velocity integral using pulsed wave Doppler echocardiography, the femoral arterial pressure, the pulmonary arterial pressure, the electrocardiogram, and the intracardiac electrocardiogram were simultaneously recorded. Results:The arterial pressure during VPC with a short coupling interval was significantly smaller regardless of the site of origin (p<0.05. The arterial pressure with VPCs originating from the RVOT was significantly more reduced than those from the RVA at a same coupling interval (p<0.05. However, the arterial pressure with originating from the LVA was insignificantly reduced than those from the RVOT. The pulmonary arterial pressure with originating from the RVOT was significantly reduced more than those from the LVA at a same coupling interval, except at the coupling interval of 500 msec (p<0.05. However, the pulmonary arterial pressure with VPCs originating from the RVA was insignificantly reduced than those from the RVOT. The aortic TVI during VPCs originating from the LVA was

Spiral CT in acute non-cardiac chest pain

Aim: Spiral CT in acute non-cardiac chest pain is usually requested to diagnose aortic dissection but a spectrum of other cardiovascular diseases may simulate this. The purpose of this study was to assess the impact of spiral computed tomography (CT) in patients with suspected aortic dissection and to determine the nature and frequency of other disorders simulating it. Methods: Over a 26-month period, all patients undergoing CT for suspected acute aortic dissection were recruited. CT was performed using a standard protocol. The CT examinations and reports were reviewed along with other relevant imaging, clinical data, surgical findings and post-mortem results. The pattern of diagnoses and their associations were evaluated. Results: Seventy-six CT examinations were performed on 70 patients of whom 47 were male. The age of the patients ranged from 24 to 84. Seven patients had previously undergone cardiothoracic surgery. Twenty-four patients had normal CT findings; 46 patients (66%) had abnormal findings. Seventy-three significant pathologies were identified including thoracic aortic aneurysm (16 cases), aortic dissection (14 cases), acute intramural aortic haematoma (nine cases), aortic rupture (eight cases), atherosclerosis (four cases) and penetrating atheromatous ulcer (two cases), pulmonary embolus (four cases), pericardial disease (12 cases) and complications following surgery (three cases). The majority of patients had a life-threatening disease. Five patients without dissection had CT findings that explained clinical pulse deficits. Conclusion: Sudden onset non-cardiac, non-pleuritic chest pain is common to several acute cardiovascular disorders. Patients have a high incidence of life-threatening disease. Of this group, classic aortic dissection is the most common diagnosis but comprises a minority of cases. Spiral CT is a reliable diagnostic test but requires conscientious technique for optimum sensitivity and accuracy. Most patients will have abnormal CT findings.

Intramural hemorrhage of the thoracic aorta: diagnosis, therapy and prognosis of 209 in vivo diagnosed cases

Aortic dissection with no entry or false lumen flow was recently identified as intramural hemorrhage of the aortic wall (IMH). Analysis of the literature revealed 209 cases of in vivo diagnosed IMH reflecting 17% of all dissections, whereas in postmortem studies this condition is found in 4-13%. Transesophageal echocardiography, computed tomography, magnetic resonance imaging and aortography (to rule out dissection) have been applied for diagnosing IMH in 57, 49, 43 and 38% of the cases, respectively. However, diagnostic accuracy of each modality is not available to date. In 34%, IMH involves the ascending aorta (type A). The average age of patients with IMH ranges between 55 and 65 years; 65% are males. In 12%, IMH was associated with abdominal aortic aneurysm. With 87%, arterial hypertension is the predominant risk factor for IMH irrespective of its location. As suggested by the term "mediastinal apoplexy" IMH may--similar to cerebral apoplexy--result from hypertensive rupture of the vasa vasorum in the aortic media. With 97%, the majority of patients present with acute chest or back pain similar to classic dissection. Mediastinal widening is found in 83%; signs of hemothorax/pleural effusion are present in 38%, acute aortic regurgitation in 26%, pericardial effusion in 23%, acute neurologic deficits in 12%, and pulse deficits in 5%. In 18%, IMH progresses to dissection and in another 15% to rupture. In 25% and 28%, respectively, dissection and rupture occur in the ascending aorta and in 12% and 9%, respectively, in the descending thoracic aorta. The 30-day mortality of IMH is 24% (36% with type A and 12% with type B IMH; p < 0.05). With surgical repair, mortality of type A IMH is lowered to 18% compared to 60% with medical treatment (p < 0.01). In contrast, with 8% mortality associated with medical treatment, prognosis of type B IMH is more favorable without surgical intervention, the latter associated with a 30-day mortality of 33% (p < 0.05). Thus, IMH is a potential precursor of dissection and should be managed like dissection with undelayed surgical intervention in patients with type A IMH and with medical treatment in type B IMH.

Aortic arch angiography prior to carotid endarterectomy. Is its continued use justified?

Patients with significant stenosis at the carotid bifurcation are traditionally subjected to four vessel aortic arch angiography prior to consideration for carotid endarterectomy. The advent of the non-invasive vascular laboratory has necessitated a reappraisal of this approach. 1. Determine the yield from aortic arch angiography and its influence on surgical management. 2. Evaluate the accuracy of clinical examination and the non-invasive vascular laboratory in the detection of aortic arch branch lesions. One hundred and twenty-nine consecutive patients undergoing evaluation for carotid endarterectomy were prospectively enrolled into the study. The protocol entailed: 1. Clinical recording of upper limb pulses, blood pressure and supraclavicular bruits. 2. Duplex scan examination to evaluate proximal inflow into the carotid arteries. 3. Four vessel aortic arch angiography to detect aortic branch lesions. Data from the non-invasive tests were compared to angiography. Patients with aortic arch branch lesions were further evaluated to determine the proportion requiring additional surgery. Nineteen patients had angiographic evidence of aortic branch disease (14.7%); six involved the common carotid artery, three the innominate artery and 10 the subclavian artery. All of these lesions were detected by the combination of unequal blood pressure, pulse deficit, bruit or duplex scan. Seven patients underwent additional surgery (5.4%) which included carotid-subclavian bypass (five), aortoinnominate bypass (one) and innominate endarterectomy (one). In patients with significant stenosis at the carotid bifurcation undergoing evaluation for carotid endarterectomy, aortic arch angiography is unnecessary except in a small percentage of patients with abnormal clinical and non-invasive findings.

Traumatic first rib fracture: is angiography necessary? A review of 730 cases

The two most common sites of first rib fracture were at the subclavian sulcus and in the neck of the first rib, posteriorly. Five distinct mechanisms for rib fracture were identified and included: (i) posteriorly directed trauma to the upper thorax or shoulder girdle; (ii) a direct blow to the sternum and anterior chest wall; (iii) a blow fracturing the clavicle; (iv) a strong sudden contraction of the scalenus anticus muscle; and (v) radiographic findings of a first rib fracture without history of trauma. Isolated first rib fracture regardless of mechanism of injury, results in a low incidence of major vascular injury (mean 3%), although with fracture displacement, the incidence is higher. First rib fracture associated with concomitant head, thoracic, abdominal, or long bone trauma was associated with vascular injury in 24% of cases. According to this review, specific indications for subclavian artery and aortic arch arteriography in patients with traumatic first rib fracture include widened mediastinum on chest radiography, upper-extremity pulse deficit, posteriroly displaced first rib fracture, subclavian groove fracture anteriorly, brachial plexus injury and expanding hematoma.

Traumatic First Rib Fracture: Is Angiography Necessary? A Review of 730 Cases

The two most common sites of first rib fracture were at the subclavian sulcus and in the neck of the first rib, posteriorly. Five distinct mechanisms for rib fracture were identified and included: (i) posteriorly directed trauma to the upper thorax or shoulder girdle; (ii) a direct blow to the sternum and anterior chest wall; (iii) a blow fracturing the clavicle; (iv) a strong sudden contraction of the scalenus anticus muscle: and (v) radiographic findings of a first rib fracture without history of trauma. Isolated first rib fracture regardless of mechanism of injury, results in a low incidence of major vascular injury (mean 3%), although with fracture displacement, the incidence is higher. First rib fracture associated with concomitant head, thoracic, abdominal, or long bone trauma was associated with vascular injury in 24% of cases. According to this review, specific indications for subclavian artery and aortic arch arteriography in patients with traumatic first rib fracture include widened mediastinum on chest radiography, upper-extremity pulse deficit, posteriorly displaced first rib fracture, subclavian groove fracture anteriorly, brachial plexus injury and expanding hematoma.