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Dive into the research topics where Warwick M. Jaffe is active.

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Featured researches published by Warwick M. Jaffe.


Journal of the American College of Cardiology | 1990

Infective endocarditis, 1983–1988: Echocardiographic findings and factors influencing morbidity and mortality

Warwick M. Jaffe; Dennis E. Morgan; Alan S. Pearlman; Catherine M. Otto

The echocardiograms and clinical records of 70 patients with infective endocarditis seen between 1983 and 1988 were examined to evaluate the role of two-dimensional and Doppler echocardiography in the diagnosis of infective endocarditis and identify risk factors for morbidity and mortality. A blinded observer reviewed the echocardiograms for the presence and size of vegetations and the severity of the valvular regurgitation. Vegetations were identified in 54 (78%) of 69 technically satisfactory echocardiograms. In 38 patients whose heart was examined at surgery or autopsy, all vegetations diagnosed by echocardiography were confirmed, but six additional vegetations were found. Abnormal (greater than or equal to 2+) valvular regurgitation was present in 88% of patients. No patient with less than or equal to 1+ regurgitation (n = 8) died or required valve surgery for heart failure, but three of the eight patients did undergo surgery for mycotic aneurysm, recurrent embolism or paravalvular abscess. In patients without embolism before echocardiography, there was a trend toward a greater incidence of subsequent embolism in those with vegetations greater than 10 mm in size (26% [8 of 31] compared with 11% [2 of 18] with vegetations less than or equal to 10 mm) (p = 0.19). By multivariate analysis, risk factors for in-hospital death (n = 7) were an infected prosthetic valve (p less than 0.007), systemic embolism (p less than 0.02) and infection with Staphylococcus aureus (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


American Journal of Cardiology | 1989

Doppler echocardiography in the assessment of the homograft aortic valve

Warwick M. Jaffe; H.Arthur Coverdale; Antony H.G. Roche; Peter W.T. Brandt; John Ormiston; Brian G. Barratt-Boyes

To determine the utility of Doppler echocardiography in the evaluation of the homograft valve in the aortic position, 27 patients with normally functioning valves (group 1) and 30 patients with suspected malfunctioning valves (group 2) were examined. Simultaneous cardiac catheterization and Doppler echocardiography were performed in 23 group 2 patients. Doppler and surgical findings were compared in 7 patients too ill for invasive studies. In group 1 patients, the maximal velocity (+/- standard deviation) was 1.8 +/- 0.37 m/s, the mean pressure gradient was 7.1 +/- 3.07 mm Hg and the mean aortic valve area was 2.2 +/- 0.79 cm2. The maximal velocity in group 2 patients with aortic regurgitation (AR) classified as moderate or greater was 2.5 +/- 0.55 m/s, compared with 1.8 +/- 0.44 m/s in patients with mild AR or less (p less than 0.01). In the quantitation of AR, pulsed-wave mapping and angiographic grades were identical in 18 patients and differed by 1 grade in 5. Seven patients too ill for catheterization had severe destruction of valve leaflets at cardiac surgery. In 6 patients, both Doppler grading methods suggested severe AR. In a seventh patient, who had an obstructed Starr-Edwards valve in the mitral position, AR was graded as mild by pulsed-wave mapping. Only 1 patient had homograft valve stenosis, with a withdrawal gradient at catheterization of 34 mm Hg and a Doppler maximal gradient of 36 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)


The Journal of Thoracic and Cardiovascular Surgery | 1998

The Medtronic Intact* porcine valve: Ten-year clinical review

Brian G. Barratt-Boyes; Warwick M. Jaffe; R. M. L. Whitlock

OBJECTIVE Our objective was to assess the long-term mortality and morbidity associated with the Medtronic Intact valve (Medtronic, Inc, Minneapolis, Minn). METHOD Between 1983 and 1996, 447 patients (280 men and 167 women) received 466 Intact valves: 280 aortic, 156 mitral, and 30 tricuspid. The mean age was 57 years (median 63 years), with 45% younger than 60 years. The mean New York Heart Association class was 3.1. The follow-up was 98% complete and extended for 39 months (1-154 months) and 1324 patient-years. There were 32 valves at risk at 10 years after implantation. Doppler echocardiography was performed whenever possible in patients followed up for longer than 4 years (mean 8 years) after implantation. RESULTS Ten-year overall actuarial survival was 30% +/- 6% (14% +/- 7% for New York Heart Association classes IV-V and 39% +/- 8% for classes I-III). At 10 years freedom from infective endocarditis was 92% +/- 3%, freedom from thromboembolism was 80% +/- 5%, and freedom from nonstructural valve deterioration was 95% +/- 2%. Ten-year freedom from explantation was 64% +/- 6%, freedom from valve-related events was 51% +/- 6%, and freedom from valve-related death was 88% +/- 3%. There were 26 examples of structural valve deterioration, mainly caused by leaflet calcification (in 17 cases) and by buttress detachment (in 6 cases). In the aortic position at 10 years freedom from structural valve deterioration was 81% +/- 9%, but with only 1 event in patients older than 40 years (freedom 92% +/- 8%) and 100% freedom in patients older than 60 years. There was also 100% freedom from structural valve deterioration in the tricuspid position. In the mitral position freedom was 65% +/- 8%, with no significant difference between age groups. CONCLUSION The Intact valve provides superior results in the aortic position in patients older than 40 years and in the tricuspid position at all ages.


Journal of Cardiac Surgery | 1991

The zero pressure fixed medtronic intact porcine valve: clinical results over a 6-year period, including serial echocardiographic assessment.

Brian G. Barratt-Boyes; Pak Hong Ko; Warwick M. Jaffe

Between 1983 and 1990, 219 patients had 224 Medtronic Intact porcine valves inserted. There were 94 aortic, 110 mitral, and 20 tricuspid valve replacements. The mean patient age was 52 years. Mean follow‐up was 33.3 months and was 97.7% complete. There was only one example of structural valve degeneration occurring at 25 months, giving an actuarial freedom of 99% at 6 years. Reoperation was performed in seven patients. At 6 years, actuarial survival was 71%, freedom from infective endocarditis 96%, freedom from thromboembolism 91%, freedom from reoperation 93%, and freedom from valve‐related complications 86%. Doppler echocardiography was performed in 48 of the 70 patients operated upon between August 1983 and October 1986 and who remained alive at the current review. Their follow‐up averaged 4.7 (3–6.7) years. The results were compared to a similar examination performed in 1987 by the same operator. No patient had significant regurgitation. Valve gradients and areas remained the same in the two studies in the mitral position (3.8 ± 1.33 mmHg) and the mean aortic gradient had reduced from 17 ± 5.2 mmHg in 1987 to 13 ± 2.8 mmHg in the current study (p = 0.02). These medium‐term results are considered encouraging.


American Journal of Cardiology | 1991

Influence of Doppler sample volume location on ventricular filling velocities

Warwick M. Jaffe; Timothy A. Dewhurst; Catherine M. Otto; Alan S. Pearlman

Abstract The ratio of peak early diastolic (E) and peak late diastolic (A) velocities, measured from the Doppler mitral waveform, has been used widely to assess left ventricular diastolic function. 1–10 This ratio is also affected by age, 2,11 heart rate 12 and loading conditions. 4,6,9 In some studies, Doppler waveforms have been recorded by sampling at the mitral anulus, 1–4 in others the sample volume has been placed between the free margins of the mitral leaflets, 5–7 and in some the measurement site has not been clearly defined. 8–10 There is no consensus regarding the optimal position. In the present study we measured E A ratio at both the mitral tips and anulus in 300 consecutive patients to determine if sample volume location had an important influence.


Eurointervention | 2015

Assessment of coronary fractional flow reserve using a monorail pressure catheter: the first-in-human ACCESS-NZ trial.

Madhav Menon; Warwick M. Jaffe; Timothy J. N. Watson; Mark Webster

AIMS FFR measurements have been limited by the handling characteristics of pressure wire (PW) systems, and by signal drift. This first-in-human study evaluated the safety and efficacy of a new monorail catheter (Navvus) to assess coronary FFR, compared to a PW system. METHODS AND RESULTS Resting measurements were acquired with both systems. After initiating IV adenosine, FFR was measured with the PW alone, simultaneously using both systems, and again with PW alone. Any zero offset of PW or Navvus was then recorded. Navvus measured FFR in all patients in whom a PW recording was obtained (50 of 58 patients); there were no complications related to Navvus. Navvus FFR correlated well with PW FFR (r=0.87, slope 1.0, intercept -0.02). Within PW measurement accuracy, in no cases did Navvus FFR classify lesion significance differently from PW FFR. PW signal drift was significantly greater than Navvus (0.06±0.12 vs. 0.02±0.02, p=0.014). CONCLUSIONS Navvus and PW FFR correlated well. Navvus had less sensor drift. This new catheter-based system offers an alternative method for measuring FFR, with some potential advantages over PW.


American Journal of Cardiology | 1988

Doppler echocardiographic assessment of atrial filling fraction in severe mitral stenosis

Warwick M. Jaffe; Antony H.G. Roche

Abstract When patients with mitral stenosis (MS) develop atrial fibrillation, symptomatic deterioration often occurs. This could be due to either loss of active atrial contraction or to the reduction in diastolic filling time caused by the tachycardia that is often present. Previous studies, using cardiac catheterization methods, have yielded conflicting results. 1–5 Recently Doppler echocardiography has been used to determine the contribution atrial contraction makes to ventricular filling in normal subjects and patients with a variety of cardiac diseases. 6 To date we are unaware of any Doppler studies in patients with MS.


The Journal of Thoracic and Cardiovascular Surgery | 1990

Rest and exercise hemodynamics of 20 to 23 mm allograft, Medtronic Intact (porcine), and St. Jude Medical valves in the aortic position.

Warwick M. Jaffe; H. A. Coverdale; A. H. G. Roche; R. M. L. Whitlock; Neutze Jm; Brian G. Barratt-Boyes


Eurointervention | 2013

First-in-human evaluation of a sirolimus-eluting coronary stent on an integrated delivery system: the DIRECT study.

Mark Webster; S. Harding; Dougal McClean; Warwick M. Jaffe; John Ormiston; Andrew Aitken; Timothy J. N. Watson


Journal of the American College of Cardiology | 2015

TCT-599 First-in-Human Evaluation of a Sirolimus-Eluitng Fixed-Wire Coronary Stent Integrated Delivery System: the Direct Study

Mark Webster; John A. Ormiston; Dougal McClean; Warwick M. Jaffe; S. Harding

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