48. Effects of nitroglycerin, trolnitrate and sodium nitrate on coronary flow and cardiac adrenergic responses

Abstracts of Papers

140

clinical evidence of heart disease, who have followed depression

in millimeters

has been correlated syndrome

as well

as with

ischemia) ,

or from

normal

manently Analysis but

the

common.

only

pressions,

can,

that

a

patient,

per-

while

but

depression.

on

the

other

may be associated

not

course

S-T

hand,

dramatic

with stable clinical

unmay

segment

continuation

of

circumflex

ventricular blood

contractile

pressure

open-chest

force,

were

Dose

injections

responses

trite-1.0 increases

in

dogs under artificial

res-

100

with

per

longed),

cent

trolnitrate,

(duration

single intravenous

to 100 N./kg.,

trolni-

sodium

ni-

pronethalol

(Netha-

were compared.

Maximal

flow (with highest

with

nitroglycerin,

and 62 per cent

of responses

was

with

also

and 46 per cent with pronethalol

doses) 36

per

sodium

most

pro-

in 3 experi-

Responses (0.03

and 0.1 pg./kg.)

(0.1

and

0.3

and

during

100

rg./kg./min.

pg./kg.)

constant

experiments), nitrate responses

for

isoprenaline

completely trolnitrate;

during

(3 and

chloride

experiments), (10

and

conditions

pronethalol also

(6

sodium (3 experi-

20

mg./kg.)

were also studied. adrenergic

noradrenaline

nitroglycerin

(50 and

of nitroglycerin

pronethalol

and inotropic and

infusions

30 min.)

under similar

Both chronotropic to

intravenous

and

were reduced

reduced

J.

and

receptors,

trolnitrate

also

responses.

GRACE,

in our

infarction

F.A.c.c.,

M.D.,

New

This

presentation

data on the attempts

60 patients

and

cardiac

that

with

arrest.

there were

cardiac

survivors. arrest

fibrillation. cessity

will report

acute

At

this

9 survivors

of

on our first hundred

at such resuscitation.

long-term

The

were

In

present

majority

addition

been

15

of the episodes

of

with

to early persistent

have

detection,

due to acute

be successfully

the neof

the

and described.

that approximately

arrest

ventricular

application

efforts will be emphasized

It is concluded can

There

associated

for sustained,

with cardiac tion

first

arrest who lived to leave the hospital.

15%

of patients

myocardial

resuscitated

infarc-

by using

our

system.

50. Microelectrode Studies on Concealed A-V Conduction, E. NEIL MOORE, D.v.M., PH.D. Philadelphia,

Pa.

Concealed

conduction

occurs

sponse fails to be propagated of transmission block

node.

thought

to

ment in the A-V node from ventricular from

electrodes single the

cells

rabbit

instances,

a

response blocked

relatively

occurred.

blocked

ventricles

failed.

Peripheral occur

between

node

right heart

premature

was sometimes

conduction

conduction

conduction

conduction

concealin the pe-

and

block,

in

preparation.

A-V

block

the bundle

of

an

isolated

The

earliest

node; nodal

In both cases, conduction

conduction

from

regions

in a given

in the A-V normal

micro-

record

other

system elicited

system. sometimes

used to simultaneously

in the A-V

specialized

perfused atria1

peripheral

were

atria1 and

concealment

specialized

from

however,

differentiate

if concealed

re-

Failure

to result

or simultaneous

electrograms,

determine

an atria1

It is not possible,

using electrocardiograms ventricular

when

to the ventricles.

is classically

in the A-V

potential

during

the

pronethalol

and

years ago we presented

responses

ionotropic

that

fl-adrenergic

adrenergic

it was reported

results

before

of

involve

WILLIAM

myocardial

bitartrate

trolnitrate

Calcium

Two

and noradrenaline

compared

actions

nitroglycerin

at resuscitation

To

also

changes

it is concluded

N. Y.

bitartrate

were

(4 experiments)

ments).

York,

isoprenaline

to intravenous

not

cardiac

M.D. and

ripheral

ments of each type.

the chrono-

*49. Resuscitation for Acute Myocardial Infarction and Cardiac Arrest, WILLIAM MINOGUE,

in left

simultaneously

and

in mean coronary

averaged

changes

to 3.0 mg./kg.,

to 10 mg./kg.,

antagonize

resuscitative

rate and femoral

following

to 30 mg./kg.,

lide@)-0.3

nitrite

heart

of nitroglycerin-O.1

do both

course

(flowmeter),

recorded

(Metamine@)-0.1

cent

studies,

flow

pentobarbitalized

piration. trate

earlier

coronary

“nitrites”

cardiac

Canada.

nitroglycerin

prevented

and the concomitant

to calcium,

vasodilator

attempts

F.A.C.C. and R. A. GILLIS, B.A., Montreal,

but neither

infusions

these findings

although

de-

Effects of Nitroglycerin, Trolnitrate and Sodium Nitrate on Coronary Flow and Cardiac Adrenergic Responses, K. I. MELVILLE, M.D.,

nitrite

responses

time

48.

In

From in

de-

and a useful life for many years.

left

to noradrenaline,

sodium

tropic effects of isoprenaline.

However,

are

clinical

ischemic,

of “is-

be correlated

exceptions

a fulminating

minor,

severity

in general,

of S-T segment

Thus,

pressions

to

and finally, with death.

suggest

disease

individual

follow

progression

electrocardiogram

impressions heart

with the extent in

of acute infarction

infarction,

tracing

nor

coronary

of these data has not yet been completed,

initial

chemic”

attacks

(subendocardial

resting

abnormal

of disability,

and decompensa-

subsequent

transmural

line

responses

of the angina1

degree

enlargement

insufficiency

RS-T

the isoelectric

of pain),

cardiac

coronary

below

with the severity

(frequency

arrhythmias, tion,

been

for many years. The extent of ischemic

cycle

in other action to the

was demonstrated

of His and right

to

bundle

THE AMERICANJOURNAL OF CARDIOLOGY