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Dive into the research topics where John A. Rizzo is active.

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Featured researches published by John A. Rizzo.


The Annals of Thoracic Surgery | 2002

Yearly rupture or dissection rates for thoracic aortic aneurysms: simple prediction based on size

Ryan R. Davies; Lee J. Goldstein; Michael A. Coady; Shawn L. Tittle; John A. Rizzo; Gary S. Kopf; John A. Elefteriades

BACKGROUNDnPrior work has clarified the cumulative, lifetime risk of rupture or dissection based on the size of thoracic aneurysms. Ability to estimate simply the yearly rate of rupture or dissection would greatly enhance clinical decision making for specific patients. Calculation of such a rate requires robust data.nnnMETHODSnData on 721 patients (446 male, 275 female; median age, 65.8 years; range, 8 to 95 years) with thoracic aortic disease was prospectively entered into a computerized database over 9 years. Three thousand one hundred fifteen imaging studies were available on these patients. Five hundred seventy met inclusion criteria in terms of length of follow-up and form the basis for the survival analysis. Three hundred four patients were dissection-free at presentation; their natural history was followed for rupture, dissection, and death. Patients were excluded from analysis once operation occurred.nnnRESULTSnFive-year survival in patients not operated on was 54% at 5 years. Ninety-two hard end points were realized in serial follow-up, including 55 deaths, 13 ruptures, and 24 dissections. Aortic size was a very strong predictor of rupture, dissection, and mortality. For aneurysms greater than 6 cm in diameter, rupture occurred at 3.7% per year, rupture or dissection at 6.9% per year, death at 11.8%, and death, rupture, or dissection at 15.6% per year. At size greater than 6.0 cm, the odds ratio for rupture was increased 27-fold (p = 0.0023). The aorta grew at a mean of 0.10 cm per year. Elective, preemptive surgical repair restored life expectancy to normal.nnnCONCLUSIONSnThis study indicates that (1) thoracic aneurysm is a lethal disease; (2) aneurysm size has a profound impact on rupture, dissection, and death; (3) for counseling purposes, the patient with an aneurysm exceeding 6 cm can expect a yearly rate of rupture or dissection of at least 6.9% and a death rate of 11.8%; and (4) elective surgical repair restores survival to near normal. This analysis strongly supports careful radiologic follow-up and elective, preemptive surgical intervention for the otherwise lethal condition of large thoracic aortic aneurysm.


Journal of the American College of Cardiology | 1998

Clinical value of acute rest technetium-99m tetrofosmin tomographic myocardial perfusion imaging in patients with acute chest pain and nondiagnostic electrocardiograms

Gary V. Heller; Stephen A. Stowers; Robert C. Hendel; Steven D Herman; Edouard Daher; Alan W. Ahlberg; Jack Baron; Carlos Mendes de Leon; John A. Rizzo; Frans J. Th. Wackers

OBJECTIVESnWe sought to evaluate the clinical use and cost-analysis of acute rest technetium-99m (Tc-99m) tetrofosmin single-photon emission computed tomographic (SPECT) myocardial perfusion imaging in patients with chest pain and a normal electrocardiogram (ECG).nnnBACKGROUNDnCurrent approaches used in emergency departments (EDs) for treating patients presenting with chest pain and a nondiagnostic ECG result in poor resource utilization.nnnMETHODSnThree hundred fifty-seven patients presenting to six centers with symptoms suggestive of myocardial ischemia and a nondiagnostic ECG underwent Tc-99m tetrofosmin SPECT during or within 6 h of symptoms. Follow-up evaluation was performed during the hospital period and 30 days after discharge. All entry ECGs, SPECT images and cardiac events were reviewed in blinded manner and were not available to the admitting physicians.nnnRESULTSnBy consensus interpretation, 204 images (57%) were normal, and 153 were abnormal (43%). Of 20 patients (6%) with an acute myocardial infarction (MI) during the hospital period, 18 had abnormal images (sensitivity 90%), whereas only 2 had normal images (negative predictive value 99%). Multiple logistic regression analysis demonstrated abnormal SPECT imaging to be the best predictor of MI and significantly better than clinical data. Using a normal SPECT image as a criterion not to admit patients would result in a 57% reduction in hospital admissions, with a mean cost savings per patient of


Cardiology Clinics | 1999

PATHOLOGIC VARIANTS OF THORACIC AORTIC DISSECTIONS: Penetrating Atherosclerotic Ulcers and Intramural Hematomas

Michael A. Coady; John A. Rizzo; John A. Elefteriades

4,258.nnnCONCLUSIONSnAbnormal rest Tc-99m tetrofosmin SPECT imaging accurately predicts acute MI in patients with symptoms and a nondiagnostic ECG, whereas a normal study is associated with a very low cardiac event rate. The use of acute rest SPECT imaging in the ED can substantially and safely reduce the number of unnecessary hospital admissions.


Cardiology Clinics | 1999

NATURAL HISTORY, PATHOGENESIS, AND ETIOLOGY OF THORACIC AORTIC ANEURYSMS AND DISSECTIONS

Michael A. Coady; John A. Rizzo; Lee J. Goldstein; John A. Elefteriades

This article confirms the existence of two variants of acute aortic pathology, the penetrating atherosclerotic ulcer (PAU) and the intramural hematoma (IMH), which are radiologically distinct from classic aortic dissection. Table 4 reviews the characteristics distinguishing PAU from classic aortic dissection and IMH. We took as a matter of definition that classic aortic dissection involves a flap which traverses the aortic lumen. We defined PAU and IMH as nonflap lesions, with PAU demonstrating a crater extending from the aortic lumen into the space surrounding the aortic lumen. This categorization can be summarized with the expression, no flap, no dissection. With these definitions made, re-review of the imaging studies for the present report identified 36 such lesions out of 214 cases originally read as aortic dissection. Therefore, these variant lesions accounted for over 1 out of 8 acute aortic pathologies. Besides confirming the existence of the conditions, PAU and IMH, as distinct radiographic lesions, this series strongly suggests that these two conditions constitute distinct clinical entities as well. Table 4 summarizes the clinical patterns of these two entities as apparent from the present study, and contrasts them with classic aortic dissections. In particular, the following observations, some of which are consonant findings in smaller series, can be made regarding the typical patient profiles of PAU and IMH from the present study: The patients with PAU and IMH are distinctly older than those with type A aortic dissection (74.0 and 73.9 versus 56.5 years, P = 0.0001). Although not statistically significant, PAU and IMH patients tend to be older than patients with type B aortic dissections as well. For PAU and IMH, unlike aortic dissection, the concentration in the elderly is manifested in a very small standard deviation of the mean age (see Fig. 13); these two entities, PAU and IMH, are essentially diseases of the seventh, eighth, and ninth decades of life. Patients with PAU and IMH are almost invariably hypertensive (about 94% of cases). The pain of PAU and IMH mimics that of classic aortic dissection, with anterior symptoms in the ascending aortic lesions and intrascapular or back pain with descending aortic lesions. Unlike classic dissection, PAU and IMH do not produce branch vessel compromise or occlusion and do not result in ischemic manifestations in the extremities or visceral organs. PAU and IMH are more focal lesions than classic aortic dissection, which frequently propagates for much or the entire extent of the thoracoabdominal aorta. PAU is uniformly associated with severe aortic arteriosclerosis and calcification, whereas classic dissection often occurs in aortas with minimal arteriosclerosis and calcification. PAU and IMH tend to occur in even larger aortas than classic aortic dissection (6.2 and 5.5 versus 5.2 cm, P = 0.01). PAU and IMH are strongly associated with AAA, which is seen concomitantly in 42.1% of PAU patients and 29.4% of IMH patients. PAU and IMH are largely diseases of the descending aorta (90% for PAU and 71% for IMH). Although our pathology data is limited, we do feel that an inherent difference in the histologic intramural level of the hematoma may underlie the pathophysiologic process that determines which patient develops a typical dissection and which develops an intramural hematoma. In particular, we feel that the level of blood collection is more superficial, closer to the adventitia, in IMH than in typical aortic dissection. This may explain why the inner layer does not prolapse into the aorta on imaging studies or when the aorta is opened in the operating room. This more superficial location would also explain the high rupture rates as compared to classic aortic dissection (Fig. 14, Table 3). We did find PAU and IMH to behave much more malignantly than typical descending aortic dissection. As seen in Figure 6, the rupture rate is much higher than for aortic dissection. Docume


Medical Care | 1998

Health Care Utilization and Costs in a Medicare Population by Fall Status

John A. Rizzo; Rebecca Friedkin; Christianna S. Williams; Janett Nabors; Denise Acampora; Mary E. Tinetti

The natural history of thoracic aortic aneurysms and dissections is diverse, reflecting a broad spectrum of etiologies which include increasing aortic size, hypertension, and genetic factors. The pathogenesis is related to defects or degeneration in structural integrity of the adventitia, not the media, which is required for aneurysm formation. The ascending and descending aorta appear to have separate underlying disease processor that lead to a weakened vessel wall and an increased susceptibility for dissection. Etiologic factors for aortic aneurysms and dissections are multifactorial, reflecting genetic, environmental, and physiologic influences.


Gastroenterology | 1994

Omeprazole versus H2-receptor antagonists in treating patients with peptic stricture and esophagitis

Robert D. Marks; Joel E. Richter; John A. Rizzo; Robert E. Koehler; Jerry G. Spenney; Thomas P. Mills; Gregory Champion

OBJECTIVESnThe economic impact of trauma in older persons is a matter of increasing concern to public health practitioners and planners, yet it is an issue that has not been widely studied. Available evidence does suggest, however, that falls are the costliest category of injury among older persons.nnnMETHODSnThis study used data from the Health Care Financing Administration and the Connecticut Long-Term Care Registry to isolate the effects of fall severity on hospital, nursing home, home health, and emergency room costs. Multivariate and logistic regression methods were used to control for the influence of a number of clinical and demographic factors believed to be independently related to health care costs. Health care costs of fallers were tracked for 1 year after the fall. The cost experience of this cohort was compared with nonfallers during the same time period.nnnRESULTSnThe results provide strong evidence that falls are associated with increased health care costs, and that this relation increases monotonically with the frequency and severity of falls. Incurring one or more injurious falls was associated with increased annual hospital costs of


The Annals of Thoracic Surgery | 1999

Surgical intervention criteria for thoracic aortic aneurysms : A study of growth rates and complications

Michael A. Coady; John A. Rizzo; Graeme L. Hammond; Gary S. Kopf; John A. Elefteriades

11,042 (1996), nursing home costs of


The Annals of Thoracic Surgery | 1999

Management of descending aortic dissection

John A. Elefteriades; Constantinos J Lovoulos; Michael A. Coady; George Tellides; Gary S. Kopf; John A. Rizzo

5,325, and total health care costs of


Clinical Therapeutics | 1997

Variations in compliance among hypertensive patients by drug class: implications for health care costs

John A. Rizzo; W. Robert Simons

19,440. Incurring two or more noninjurious falls increased costs substantially as well.nnnCONCLUSIONSnThe health care costs of falls are pervasive and substantial, and they increase with fall frequency and severity.


Journal of Health Economics | 1994

Physician labor supply: do income effects matter?

John A. Rizzo; David Blumenthal

BACKGROUND/AIMSnAlthough dysphagia in patients with peptic stricture is attributed to a decreased luminal diameter, coexistent esophagitis may be an equally important cause. The goals of this study were to determine whether medical healing of esophagitis in patients with stricture improves dysphagia and decreases dilatation need and to compare the efficacy and cost-effectiveness of omeprazole versus H2-receptor antagonists (H2RA).nnnMETHODSnThirty-four dysphagic patients with peptic stricture and erosive esophagitis were dilated and randomized to omeprazole 20 mg every day versus H2RA (ranitidine 150 mg twice daily or famotidine 20 mg twice daily). Patients received further dilatations only if dysphagia frequency was greater than or equal to once per week. At 3 and 6 months, patients were assessed for esophagitis healing, dysphagia relief, and bougienage requirements. Cost-effectiveness of omeprazole and H2RA was determined.nnnRESULTSnPatients with healed esophagitis at 3 and 6 months were more likely to dysphagia-free and to require fewer dilatations than patients with persistent esophagitis. At 6 months, omeprazole produced a significantly (P < 0.01) higher rate of esophagitis healing, dysphagia relief, and fewer dilatations compared with H2RA. Omeprazole was also 40%-50% more cost-effective.nnnCONCLUSIONSnEsophagitis healing improves dysphagia and decreases dilatation need in patients with peptic stricture. Omeprazole heals esophagitis and relieves dysphagia more efficaciously than H2RA while decreasing costs to patients.

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Paul S. Calem

Federal Reserve Bank of Philadelphia

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