PaO2 increases with coughing in patients with chronic lung disease

We considered if the cyanosis frequently observed during a cough attack in patients with chronic lung disease was due to worsening hypoxemia. To investigate the effects of cough on PaO2, we measured arterial blood gases before and after a voluntary coughing period of 45 sec, in 11 patients with Interstitial Lung Disease (ILD) and 14 patients with Chronic Obstructive Lung Disease (COPD). All patients significantly increased (p less than 0.05) their PaO2 (COPD: from 49 +/- 2 to 60 +/- 2 mmHg; ILD from 44 +/- 2 to 51 +/- 3 mmHg, mean +/- SD) and decreased their PaCO2. We conclude that stable patients with COPD and ILD increase their PaO2 with coughing most likely due to hyperventilation. The cyanosis observed could be due to peripheral circulatory effects of coughing.     

Primary reperfusion in acute right ventricular infarction: An observational study简

AIM: To investigate the impact of primary reperfusion therapy (RT) on early and late mortality in acute right ventricular infarction (RVI).METHODS: RVI patients (n = 679) were prospectively classified as without right ventricular failure (RVF) (class A, n = 425, 64%), with RVF (class B, n = 158, 24%) or with cardiogenic shock (CS) (class C, n = 96, 12%). Of the 679 patients, 148 (21.7%) were considered to be eligible for thrombolytic therapy (TT) and 351 (51.6%) for primary percutaneous coronary intervention (PPCI). TIMI 3-flow by TT was achieved for A, B and C RVI class in 65%, 64% and 0%, respectively and with PPCI in 93%, 91% and 87%, respectively.RESULTS: For class A without RT, the mortality rate was 7.9%, with TT was reduced to 4.4% (P < 0.01) and with PPCI to 3.2% (P < 0.01). Considering TT vs PPCI, PPCI was superior (P < 0.05). For class B without RT the mortality was 27%, decreased to 13% with TT (P < 0.01) and to 8.3% with PPCI (P < 0.01). In a TT and PPCI comparison, PPCI was superior (P < 0.01). For class C without RT the in-hospital mortality was 80%, with TT was 100% and with PPCI, the rate decreased to 44% (P < 0.01). At 8 years, the mortality rate without RT for class A was 32%, for class B was 48% and for class C was 85%. When PPCI was successful, the long-term mortality was lower than previously reported for the 3 RVI classes (A: 21%, B: 38%, C: 70%; P < 0.001).CONCLUSION: PPCI is superior to TT and reduces short/long-term mortality for all RVI categories. RVI CS patients should be encouraged to undergo PPCI at a specialized center.     

Behavior of the pulmonary circulation at rest and during exercise in miliary tuberculosis

We studied the hemodynamic behavior of the pulmonary circulation at rest and during exercise in six patients with MTB. As a group, in contrast to advanced fibrocaseous tuberculosis, these patients exhibited normal pulmonary hemodynamics at rest and during exercise. Only minor abnormalities in pulmonary vascular resistance at exercise (increased PAd-PWP gradient) were noted in two of the patients. The increase in Rp during exercise does not appear to be related to acute hypoxic vasoconstruction but rather to functional changes (compliance or recruitment or both) of the pulmonary microvasculature. In the genesis of these functional changes, chronic alveolar hypoxia and the inflammatory-fibrotic process might be interacting.     

Clinical-Echocardiographic Correlation of Myocardial Infarction with Extension to Right Chambers

In order to determine the transesophageal echocardiographic characteristics in patients with acute myocardial infarction of right ventricle and establish the relationship between these findings, the clinical condition, and their prognostic value, 38 patients consecutively admitted to the Instituto Nacional de Cardiología with a diagnosis of acute left ventricular myocardial infarction with extension to right ventricle and/or atrium were retrospectively studied. Of the left ventricular infarctions, 37 were posteroinferior and one anterior. Significant elevations of CPK and DHL were found in 35. In 30 patients (78%) electrocardiographic evidence of extension of infarction to the right ventricle was found, and in 3, evidence of right atrial infarction. Twenty-one patients presented clinical data compatible with right ventricular infarction. In 19, cardiac rhythm and atrioventricular conduction disturbances were documented. Coronary angiograms practiced on 34 patients demonstrated single-vessel (right coronary) disease in 12, affection of two vessels in 14, and lesions in three or more in 6. Coronary arteries presented no significant lesions in two cases. With TEE, alterations of right ventricular segmental mobility were demonstrated in all patients, and in 6, alterations of right atrial mobility as well. As respects the ventricular wall movement index, 68.5% had total scores (RV + LV) of <5. The other 31.5% had scores >/= 5. In 26%, the right ventricular wall movement index was >/=4. The RVDD/LVDD ratio was 1 or less in 30 patients (78%) and >1 in only 8 (22%). The conclusions from these findings are that: (1) TEE is an excellent diagnostic means of identifying right ventricular and/or atrial infarction; and (2) a relationship exists between the magnitude of right ventricular damage and a wall movement index of 5 or more or an RV/LV diastolic diameter ratio > 1:postinfarction hemodynamic deterioration is significantly greater and the incidence of intrahospitalary complications higher.     

PaO2 increases with coughing in patients with chronic lung disease

We considered if the cyanosis frequently observed during a cough attack in patients with chronic lung disease was due to worsening hypoxemia. To investigate the effects of cough on PaO₂, we measured arterial blood gases before and after a voluntary coughing period of 45 sec, in 11 patients with Interstitial Lung Disease (ILD) and 14 patients with Chronic Obstructive Lung Disease (COPD). All patients significantly increased (p < 0.05) their PaO₂ (COPD: from 49 ± 2 to 60 ± 2 mmHg; ILD from 44 ± 2 to 51 ± 3 mmHg, mean ± SD) and decreased their PaCO₂. We conclude that stable patients with COPD and ILD increase their PaO₂ with coughing most likely due to hyperventilation. The cyanosis observed could be due to peripheral circulatory effects of coughing.     

The effect of gelfoam embolism in vascular conduction and critical pressure in the isolated canine lobe

Pulmonary pressure-flow curves, hemodynamic and blood gas parameters in West's zone II condition were obtained in nine isolated in situ left lower lobes (LLL) before (condition A), and after 15, 30 and 60 minutes of lobar gelfoam embolization (GE) (condition B) in order to know the natural history of this model. After GE a decrease in PaO2 and lobar O2 were noticed (p less than 0.05). Vascular conductance (p less than 0.001) and lobar blood flow decreased (p less than 0.05), accompanied by a significant increase in the inflow (p less than 0.01) and in the mean closing pressures (p less than 0.01). These parameters did not change during the time of observation at condition B. Nor the cardiac output or the minimal closing pressure changed in relation to condition A. LLL angiographic findings showed evidence of arterial occlusion and the pattern of obstruction was not homogeneous. Lobes histology showed occluded arteries of more than 300 micrometers of diameter. We concluded that in this canine model of increased pulmonary vascular resistance, pulmonary vascular conductance and mean closing pressure change, remain stable during 60 minutes after GE allowing us to know the natural history of the preparation. Condition than allow to perform and evaluate other interventions on lung vascular mechanics in the experimental setting of pulmonary embolization.     

Risk factors, echocardiographic patterns, and outcomes in patients with acute ventricular septal rupture during myocardial infarction

Ventricular septal rupture (VSR), which can complicate an acute myocardial infarction (MI), carries a high mortality rate. Because precordial and transesophageal echocardiography can identify the type of rupture and assess right ventricular (RV) function at the patient's bedside, we examined the prognostic significance of echocardiographic patterns in postinfarct VSR by postulating that complex rupture and RV involvement carry a worse prognosis. Seventeen patients (10 men; mean age 66 years) who had confirmed postinfarct VSR underwent precordial and transesophageal echocardiography followed by coronary angiography. Serial 12-lead and right precordial leads were also available. Type of septal rupture was classified as simple or complex based on autopsy-proved echocardiographic criteria. Three patients had inferior wall MI and 14 had anterior wall MI. ST-segment elevation persisted >72 hours in all 3 patients who had inferior wall MI and in 12 who had anterior wall MI. Segmental wall motion abnormalities helped in detecting the left ventricular entry site, and use of unconventional views superimposed with color flow Doppler provided the RV exit site. RV function was better appreciated with transesophageal echocardiography. Two patients who had inferior wall MI and 7 who had anterior wall MI had complex ruptures. All 3 patients who had inferior wall MI and 7 who had anterior wall MI had electrocardiographic and echocardiographic evidence of RV involvement. Mortality rate was higher in patients who had complex rupture (78% vs 38%, p <0.001) and in those who had RV extension (71% vs 29%, p <0.001). In conclusion, persistent ST elevation is a common finding in patients who have postinfarct VSR. Complex VSR and RV involvement are significant determinants of clinical outcome.     

Hemodynamic effect of hydralazine in interstitial lung disease patients with cor pulmonale. Immediate and short-term evaluation at rest and during exercise

Hydralazine was administered short-term to 13 patients who had stable interstitial lung disease (ILD), pulmonary arterial hypertension (PAH); mean pulmonary arterial pressure ( [PAP]=26 +/- 9 mm Hg), and cor pulmonale (CP). All patients were studied at rest and during exercise. After intravenous hydralazine at rest, there were statistically significant increases in cardiac index (CI) (p less than 0.001), arterial oxygen saturation (SaO2) (p less than 0.01), and mixed venous saturation (S-vO2) (p less than 0.01). Pulmonary vascular resistance (Rp) (p less than 0.005) and systemic resistance (Rs) decreased (p less than 0.001), and PAP did not change. During exercise, PAP did not change; however, CI (p less than 0.01), PaO2 (p less than 0.001), and S-vO2 (p less than 0.01) increased further. The increase in Rp was significantly reduced (p less than 0.01). After continuation of oral hydralazine therapy in 12 patients for 7 days, PAP at rest was not statistically different from control; Rp and Rs remained decreased (p less than 0.001). The same results were found for CI, PaO2, S-vO2, and Rs during exercise. Although PAP did not change from control values, the drug significantly reduced the increase in Rp (p less than 0.005). Vasodilator therapy with hydralazine could be useful in patients with stable ILD who have inflammation with minimal to moderate fibrosis and PAH and might be used as an adjunct to conventional therapy for ILD and CP.     

Myocardial perfusion scintigraphy (SPECT) in the evaluation of patients in the emergency room with precordial pain and normal or doubtful ischemic ECG. Study 60 cases

OBJECTIVES: To evaluate the diagnostic utility of myocardial perfusion by SPECT and Gated-SPECT in the diagnosis of acute coronary syndrome in patients with precordial pain associated with normal or doubtful ischemic ECG within the first 6 hrs of the last episode of pain. METHODS: Sixty such patients who sought attention in the Emergency room were included. Myocardial perfusion SPECT and Gated-SPECT (GSPECT) was performed in all patients using two distinct protocols. All patients underwent resting and pharmacological stress test. In 30 cases coronary angiogram were performed. RESULTS: Resting myocardial perfusion was abnormal or positive in 25 patients (42%) and normal or negative in 35 patients (58%). In the latter group perfusion became abnormal in 15 patients (43%) under stress with dipyridamole, while it remained normal in 19 (54%). The last subgroup presented no coronary events during the 12 months following their hospital discharge. In the group of 25 patients with resting perfusion abnormalities acute myocardial infarction was diagnosed in 7 patients, ischemia in 12 and reverse-reversibility in 6. Myocardial perfusion scintigraphy showed in the resting phase a low sensitivity of 61% (95% CI 39-74%), and negative predictive value of 71% (95% CI, 58-82%). During the stress phase, the utility of the test increased significantly, with a sensitivity of 97% (95% CI, 83-99%), specificity of 79% (95% CI, 57-92%), positive predictive value of 87% (95% CI, 72-95%) and, most outstanding, a negative predictive value of 95% CI, 73-99%). CONCLUSIONS: Myocardial perfusion studies have a sensitivity of 97% for identifying patients with acute coronary syndrome, with precordial pain and normal or doubtful ischemic ECG. For the intermediate or low risk patients with acute coronary syndrome the non-invasive diagnostic techniques of SPECT and GSPECT systems of evaluating myocardial perfusion achieve a high degree diagnostic accuracy, safety and reduces unnecessary admissions and costs.