The effects of aging on arterial mechanical properties and the response to nitroprusside were examined in 25 patients with dilated cardiomyopathy. High-fidelity pressures were recorded with a multisensor catheter. Pulse wave velocity was determined between two sensors in the thoracic aorta. Arterial compliance was determined by an analysis of the diastolic waveform and cardiac output.At baseline, despite a similar systemic vascular resistance, the pulsatile load (e.g., arterial compliance) and wave transmission characteristics (e.g., pulse wave velocity) were altered with aging. Arterial compliance was reduced in older (> 50 yr, n = 8) versus younger (< 35 yr, n = 8) patients (0.51±0.17 vs.1.33±0.63 ml/mmHg, P < 0.01) and intermediate in those 35-50 yr of age (n = 9,0.72±0.40 ml/mmHg). There was a positive correlation between age and pulse wave velocity (r = +0.90).Nitroprusside infusion decreased resistance, increased arterial compliance, and lowered pulse wave velocity in all groups. Yet, advancing age was associated with a greater fall in wave velocity for a given fall in aortic pressure. The slope (K) of the relation between pulse wave velocity and aortic diastolic pressure progressively increased with age (0.01±0.03, 0.06±0.02, and 0.09±0.03 m/s-mmHg). Multiple linear regression analysis revealed a significant relation between K and age.These data demonstrate that in older patients with dilated cardiomyopathy the left ventricle is coupled to an arterial circulation that has a greater pulsatile load, despite a similar steady load. Furthermore, these age-related changes in the arterial system affect the hemodynamic response to pharmacologicallyinduced vasodilatation. (J. Clin.

There has been recent interest in carotid restenosis following endarterectomy. To evaluate the significance of this complication, 2549 consecutive patients who were evaluated for suspected carotid artery occlusive disease by carotid phonoangiography, ocular plethysmography, and B-mode scanning techniques over a 21-month period were reviewed. Within this group a total of 155 patients had previously undergone a carotid endarterectomy. Of these, only four patients manifested clinically significant restenosis. In the majority of patients the carotid bifurcation was free of significant disease. The "carotid shelf" that represents the superior aspect of residual intimal plaque following endarterectomy could be clearly identified in the early postoperative period; however, it later blended to become less distinct. In a few instances, however, the amount of residual plaque at the lower extent of the endarterectomy was very prominent and remained so during follow-up studies, suggesting the possibility that this might represent a focus for future thrombosis. We conclude that noninvasive testing as used herein is an accurate method of assessing the carotid artery following endarterectomy. The accuracy of these techniques has been of such high degree that 16 carefully selected patients have subsequently undergone carotid endarterectomy without preoperative angiography.

There has been recent interest in carotid restenosis following endarterectomy. To evaluate the significance of this complication, 2549 consecutive patients who were evaluated for suspected carotid artery occlusive disease by carotid phonoangiography, ocular plethysmography, and B-mode scanning techniques over a 21-month period were reviewed. Within this group a total of 155 patients had previously undergone a carotid endarterectomy. Of these, only four patients manifested clinically significant restenosis. In the majority of patients the carotid bifurcation was free of significant disease. The "carotid shelf" that represents the superior aspect of residual intimal plaque following endarterectomy could be clearly identified in the early postoperative period; however, it later blended to become less distinct. In a few instances, however, the amount of residual plaque at the lower extent of the endarterectomy was very prominent and remained so during follow-up studies, suggesting the possibility that this might represent a focus for future thrombosis. We conclude that noninvasive testing as used herein is an accurate method of assessing the carotid artery following endarterectomy. The accuracy of these techniques has been of such high degree that 16 carefully selected patients have subsequently undergone carotid endarterectomy without preoperative angiography.